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Questions and Answers

Which of the following numbers is NOT a natural number?

  • 1
  • 100
  • 5
  • 0 (correct)

Which set includes zero and all positive integers?

  • Rational numbers
  • Whole numbers (correct)
  • Natural numbers
  • Integers

Which of the following is an example of an integer?

  • $\sqrt{2}$
  • -5 (correct)
  • $ rac{1}{2}$
  • 3.14

Which of the following numbers is a rational number?

<p>$\frac{2}{3}$ (D)</p> Signup and view all the answers

Which set encompasses both rational and irrational numbers?

<p>Real numbers (D)</p> Signup and view all the answers

Which of the following is an example of a non-real number?

<p>$\sqrt{-4}$ (D)</p> Signup and view all the answers

How can a rational number be expressed?

<p>As a fraction of two integers (A)</p> Signup and view all the answers

Which of the following is a characteristic of irrational numbers?

<p>Their decimal expansions are non-repeating and non-terminating. (A)</p> Signup and view all the answers

Which type of decimal number is always a rational number?

<p>Terminating decimals (A)</p> Signup and view all the answers

What is the first step in converting a recurring decimal into a rational number?

<p>Multiply $x$ by a power of 10. (A)</p> Signup and view all the answers

When is a decimal form considered rational?

<p>When it is either terminating or repeating (B)</p> Signup and view all the answers

What mathematical operation transforms an irrational number into a rational approximation?

<p>Rounding off (B)</p> Signup and view all the answers

What determines the rounding direction when rounding off a decimal number?

<p>The digit after the required decimal place (C)</p> Signup and view all the answers

What happens to the digit to be rounded up if it is 9?

<p>It becomes 0 and the preceding digit is rounded up by 1 (D)</p> Signup and view all the answers

What is a surd?

<p>The $n$-th root of a number that cannot be simplified to a rational number (B)</p> Signup and view all the answers

Which of the following is NOT a surd?

<p>$\sqrt{4}$ (C)</p> Signup and view all the answers

What should you identify first when estimating surds?

<p>The nearest perfect powers (B)</p> Signup and view all the answers

What is the numerical factor in a term called?

<p>Coefficient (A)</p> Signup and view all the answers

What is a term without a variable called?

<p>Constant (B)</p> Signup and view all the answers

What is an expression with two terms called?

<p>Binomial (B)</p> Signup and view all the answers

Which of the following correctly represents the product of two binomials $(ax + b)(cx + d)$?

<p>$acx^2 + adx + bcx + bd$ (B)</p> Signup and view all the answers

What is the mathematical process of breaking down an expression into simpler expressions that, when multiplied together, give the original expression?

<p>Factorisation (C)</p> Signup and view all the answers

Which of the following is the correct factorisation of the difference of two squares $a^2 - b^2$?

<p>$(a + b)(a - b)$ (D)</p> Signup and view all the answers

Which of the following is the correct factorisation of the sum of two cubes $x^3 + y^3$?

<p>$(x + y)(x^2 - xy + y^2)$ (D)</p> Signup and view all the answers

What is the first step in simplifying algebraic fractions?

<p>Factorising the numerator and the denominator (A)</p> Signup and view all the answers

What operation is equivalent to dividing by a fraction?

<p>Multiplying by the reciprocal of the fraction (D)</p> Signup and view all the answers

Which of the following numbers is both rational and an integer?

<p>-7 (B)</p> Signup and view all the answers

Which of the following expressions represents the correct procedure for multiplying a binomial $(A + B)$ and a trinomial $(C + D + E)$?

<p>$A(C + D + E) + B(C + D + E)$ (B)</p> Signup and view all the answers

Given that $x$ is a real number and $x^2 = -1$, what type of number is $x$?

<p>Imaginary number (C)</p> Signup and view all the answers

What is the result of simplifying the following expression: $\frac{x^2 - 4}{x + 2}$?

<p>$x - 2$ (B)</p> Signup and view all the answers

How would you classify the number $0.12345678910111213...$?

<p>Irrational Number (D)</p> Signup and view all the answers

If $a$ and $b$ are irrational numbers, which of the following statements is always true?

<p>None of the above (D)</p> Signup and view all the answers

Evaluate and simplify: $\frac{x^3 + y^3}{x + y}$

<p>$x^2 - xy + y^2$ (C)</p> Signup and view all the answers

Let $S = \sqrt{2} + \sqrt{3}$. Which of the following statements is correct?

<p>$S$ is a surd (B)</p> Signup and view all the answers

To which set of numbers does $0$ belong, but $1$ does not?

<p>Whole numbers (A)</p> Signup and view all the answers

Which of the following correctly describes the relationship between integers ($Z$) and whole numbers ($N_0$)?

<p>$N_0$ is a subset of $Z$ (C)</p> Signup and view all the answers

Which of the following numbers is classified as an irrational number?

<p>$\pi$ (C)</p> Signup and view all the answers

Which of the following statements is true regarding real numbers?

<p>Real numbers include both rational and irrational numbers. (D)</p> Signup and view all the answers

What distinguishes an imaginary number from a real number?

<p>Imaginary numbers, when squared, result in a negative number. (B)</p> Signup and view all the answers

Which of the following numbers can be expressed in the form $\frac{a}{b}$, where $a$ and $b$ are integers and $b \neq 0$?

<p>$\frac{7}{8}$ (B)</p> Signup and view all the answers

Which statement accurately describes irrational numbers?

<p>Their decimal representations are non-repeating and non-terminating. (D)</p> Signup and view all the answers

Which of the following decimal forms is characteristic of rational numbers?

<p>Non-terminating and repeating (D)</p> Signup and view all the answers

When converting the recurring decimal $0.\overline{3}$ into a rational number, what is a crucial initial step?

<p>Multiply $0.\overline{3}$ by 10 (C)</p> Signup and view all the answers

Under what condition is a decimal form regarded as representing a rational number?

<p>If it is terminating or repeating (C)</p> Signup and view all the answers

Which operation is typically used to transform an irrational number into a rational approximation?

<p>Rounding off (B)</p> Signup and view all the answers

What factor determines the direction to round when approximating a decimal number?

<p>The digit immediately following the desired decimal place (B)</p> Signup and view all the answers

What adjustment is made if the digit to be rounded up is a '9'?

<p>The '9' becomes a '0', and the preceding digit is increased by one (A)</p> Signup and view all the answers

What is a surd fundamentally?

<p>The $n$-th root of a number that cannot be simplified to a rational number. (B)</p> Signup and view all the answers

Which of the following is not considered a surd?

<p>$\sqrt{16}$ (C)</p> Signup and view all the answers

What is the primary initial step in estimating surds?

<p>Identify the nearest perfect powers (B)</p> Signup and view all the answers

In the algebraic term $5x^2$, what is the coefficient?

<p>$5$ (C)</p> Signup and view all the answers

What is the correct terminology for a term in an algebraic expression that does not contain a variable?

<p>Constant (C)</p> Signup and view all the answers

What is the name given to an algebraic expression that consists of precisely two terms?

<p>Binomial (B)</p> Signup and view all the answers

What is the result of applying the distributive property to multiply a monomial $a$ with a binomial $(x + y)$?

<p>$ax + ay$ (C)</p> Signup and view all the answers

What is the inverse operation of expanding algebraic expressions?

<p>Factorisation (B)</p> Signup and view all the answers

What is the result of completely factorising the expression $4x^2 - 9$?

<p>$(2x + 3)(2x - 3)$ (B)</p> Signup and view all the answers

How does the sum of two cubes, $a^3 + b^3$, factorise?

<p>$(a + b)(a^2 - ab + b^2)$ (D)</p> Signup and view all the answers

What is the initial step in simplifying a complex algebraic fraction?

<p>Factorising the numerator and denominator (C)</p> Signup and view all the answers

Which operation is mathematically equivalent to division by a fraction?

<p>Multiplying by the reciprocal of the fraction (C)</p> Signup and view all the answers

Which expression accurately shows the product of a binomial $(P + Q)$ and a trinomial $(R + S + T)$?

<p>$P(R + S + T) + Q(R + S + T)$ (A)</p> Signup and view all the answers

Given that $x$ is a non-zero real number, how would you classify $\frac{1}{x}$?

<p>Can be rational or irrational depending on $x$. (D)</p> Signup and view all the answers

Simplify the expression: $\frac{x^2 - 9}{x - 3}$

<p>$x + 3$ (A)</p> Signup and view all the answers

How would you categorise the number $3.141592653589793...$?

<p>An irrational number. (B)</p> Signup and view all the answers

If $p$ is a rational number and $q$ is an irrational number, what can be said about $p + q$?

<p>Always an irrational number. (D)</p> Signup and view all the answers

Simplify the expression: $\frac{a^3 - b^3}{a - b}$

<p>$a^2 + ab + b^2$ (C)</p> Signup and view all the answers

Consider $T = \sqrt{5} - \sqrt{2}$. Which of the following statements accurately describes $T$?

<p>$T$ is an irrational number. (C)</p> Signup and view all the answers

Which of the following numbers is an element of the set of integers but not of the set of natural numbers?

<p>-1 (B)</p> Signup and view all the answers

How many integer solutions exist for the equation $x^2 = 5$?

<p>0 (A)</p> Signup and view all the answers

Given the expression $P = (A + B)^2$, where $A$ is rational and $B$ is irrational, what can generally be said about $P$?

<p>$P$ can be rational or irrational, depending on $A$ and $B$. (D)</p> Signup and view all the answers

Identify the correct factorisation of the quadratic trinomial $x^2 + 5x + 6$.

<p>$(x + 2)(x + 3)$ (B)</p> Signup and view all the answers

Which number is both a whole number and an integer but not a natural number?

<p>0 (B)</p> Signup and view all the answers

Consider the number $N = 0.123123123...$ where the digits '123' repeat indefinitely. Is $N$ rational or irrational?

<p>Rational, because it's a repeating decimal. (D)</p> Signup and view all the answers

Which set of numbers does $\sqrt[3]{-8}$ belong to?

<p>Rational and Integers. (D)</p> Signup and view all the answers

Suppose $x$ and $y$ are two irrational numbers such that $x = \sqrt{a}$ and $y = \sqrt{b}$ where $a$ and $b$ are distinct prime numbers. Which of the following is true about their product $xy$?

<p>xy is always an irrational number. (C)</p> Signup and view all the answers

Define $f(x) = x + \frac{1}{x}$ for all non-zero real numbers $x$. What type of number is $f(\sqrt{2})$?

<p>An irrational number. (A)</p> Signup and view all the answers

Which set of numbers includes all integers and their fractional parts?

<p>Rational Numbers (A)</p> Signup and view all the answers

Which of the following numbers is an element of the set of whole numbers?

<p>0 (B)</p> Signup and view all the answers

Which of the following is considered a non-real number?

<p>$\sqrt{-4}$ (D)</p> Signup and view all the answers

Which of the following statements correctly describes the relationship between the sets of numbers?

<p>All natural numbers are integers. (D)</p> Signup and view all the answers

If a decimal number is non-terminating and non-repeating, to which set does it belong?

<p>Irrational Numbers (D)</p> Signup and view all the answers

What is the key characteristic that distinguishes rational numbers from irrational numbers?

<p>Rational numbers can be expressed as a ratio of two integers. (B)</p> Signup and view all the answers

What is the decimal representation of a rational number?

<p>Either terminating or repeating. (C)</p> Signup and view all the answers

When converting a recurring decimal to a rational number, what is the purpose of multiplying by a power of $10$?

<p>To shift the decimal point so that the recurring pattern aligns for subtraction. (A)</p> Signup and view all the answers

What happens to an irrational number when it is rounded off to a certain number of decimal places?

<p>It becomes a rational number. (A)</p> Signup and view all the answers

In the process of rounding off a decimal number, what action is taken if the digit immediately following the desired decimal place is 4?

<p>Leave the last digit of the required decimal place unchanged. (B)</p> Signup and view all the answers

During the rounding of a decimal number to a specific decimal place, what adjustment is made to the preceding digit if the digit to be rounded up is $9$?

<p>The $9$ is replaced with a $0$, and the preceding digit is increased by $1$. (C)</p> Signup and view all the answers

Which of the following expressions represents a surd?

<p>$\sqrt{5}$ (A)</p> Signup and view all the answers

Before estimating the value of $\sqrt{11}$, what should you identify?

<p>The nearest perfect squares to $11$. (A)</p> Signup and view all the answers

In the algebraic expression $7x^3$, what is the coefficient?

<p>$7$ (D)</p> Signup and view all the answers

What do you call a term in an algebraic expression that does not contain any variables?

<p>Constant (D)</p> Signup and view all the answers

An algebraic expression consisting of exactly two terms is called a what?

<p>Binomial (C)</p> Signup and view all the answers

What is the product of the monomial $3a$ and the binomial $(2x + y)$?

<p>$6ax + 3ay$ (A)</p> Signup and view all the answers

What is the name of the process that reverses expansion, expressing an algebraic expression as a product of its factors?

<p>Factorisation (A)</p> Signup and view all the answers

What is the factorisation of the expression $9x^2 - 16$?

<p>$(3x - 4)(3x + 4)$ (A)</p> Signup and view all the answers

How does the expression $x^3 + 8$ factorise?

<p>$(x + 2)(x^2 - 2x + 4)$ (B)</p> Signup and view all the answers

When simplifying algebraic fractions, what is the first step?

<p>Factorise the numerator and denominator. (A)</p> Signup and view all the answers

What is the classification of $\sqrt{-9}$?

<p>Non-Real Number (B)</p> Signup and view all the answers

What is the simplified form of the algebraic fraction $\frac{x^2 - 1}{x + 1}$?

<p>$x - 1$ (C)</p> Signup and view all the answers

Which of the following is true for any integer $n$?

<p>$n$ is always a rational number (B)</p> Signup and view all the answers

If $p$ is a rational number and $q$ is an irrational number, then what is $p + q$?

<p>Always irrational (A)</p> Signup and view all the answers

Consider $X = \sqrt{3} + 1$. Which of the following is true?

<p>$X$ is irrational (B)</p> Signup and view all the answers

Which of the following numbers belongs in the set of integers, but not in the set of natural numbers?

<p>0 (A)</p> Signup and view all the answers

How many real roots does the equation $x^2 + 1 = 0$ have?

<p>0 (C)</p> Signup and view all the answers

Given the number $N = 0.33333...$ where the digit $3$ repeats indefinitely. What type of number is $N$?

<p>Rational (B)</p> Signup and view all the answers

To which set of numbers does the result of $\sqrt[3]{-1}$ belong?

<p>Both integers and rational numbers (B)</p> Signup and view all the answers

Suppose $x$ and $y$ are irrational numbers. Which of the following must always be true?

<p>Neither the sum nor the product is necessarily rational or irrational. (D)</p> Signup and view all the answers

Given that $a$ and $b$ are positive integers, and $a$ is a factor of $b$, what type of number is $\frac{b}{a}$?

<p>Always rational (D)</p> Signup and view all the answers

Let $f(x) = x + \frac{1}{x}$ for all non-zero real numbers $x$. What type of number is $f(\sqrt{3})$?

<p>Irrational (A)</p> Signup and view all the answers

Let's define a new operation $\star$ such that $a \star b = a^2 + b$, where $a$ is an irrational number and $b$ is a rational number. What can be said about the result of $a \star b$?

<p>It is always irrational. (C)</p> Signup and view all the answers

Define an operation $\S$ such that for any two real numbers $x$ and $y$, $x \S y = \frac{x + y}{xy}$. If both $x$ and $y$ are irrational, is $x \S y$ necessarily irrational?

<p>No, it could be rational or irrational depending on the values of $x$ and $y$. (B)</p> Signup and view all the answers

For what real number $x$ is $\frac{1}{1 + \frac{1}{1 + x}}$ not defined?

<p>$x = -1$ (A)</p> Signup and view all the answers

What is the simplified form of the expression: $\frac{a^2-b^2}{a+b} - \frac{a^3+b^3}{a^2-ab+b^2}$?

<p>0 (C)</p> Signup and view all the answers

Flashcards

Natural Numbers (N)

Positive integers starting from 1, represented by the symbol N.

Whole Numbers (N0)

Natural numbers plus zero; symbol is N0.

Integers (Z)

Includes whole numbers and their negative counterparts; symbol is Z.

Rational Numbers (Q)

Numbers expressible as a fraction ( \frac{a}{b} ) where a and b are integers and ( b \neq 0 ); symbol is Q.

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Irrational Numbers (Q')

Numbers that cannot be expressed as a simple fraction; their decimal expansions are non-repeating and non-terminating; symbol is Q'.

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Real Numbers (R)

Include all rational and irrational numbers; symbol is R.

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Imaginary Numbers

Numbers that have a negative square root.

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Rational Number (Q)

A number that can be written in the form ( \frac{a}{b} ), where a and b are integers and ( b \neq 0 ).

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Irrational Numbers (Q')

Numbers that cannot be written as a fraction with integer numerator and denominator.

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Rounding Off

A method to simplify a decimal number to a required number of decimal places.

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Surd

The (n)-th root of a number that cannot be simplified to a rational number.

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Term

A single mathematical entity.

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Expression

A combination of terms.

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Coefficient

The numerical factor in a term.

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Exponent

The power to which a base is raised.

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Base

The variable or number being raised to a power.

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Constant

A term without a variable.

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Variable

A symbol representing an unknown quantity.

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Equation

A statement that two expressions are equal.

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Monomial

An expression with one term.

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Binomial

An expression with two terms.

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Trinomial

An expression with three terms.

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Factorisation

Breaking down an expression into simpler expressions (factors).

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Common Factors

Identifying and extracting a factor common to all terms in the expression.

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Difference of Two Squares

Factorising using the identity: ( a^2 - b^2 = (a + b)(a - b) )

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Factorising by Grouping

Grouping terms with common factors and then factorising each group.

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Factorising a Quadratic Trinomial

Breaking down a quadratic in the form (ax^2 + bx + c) into binomial factors.

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Sum of Two Cubes

Breaking down the form (x^3 + y^3 = (x + y)(x^2 - xy + y^2)).

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Difference of Two Cubes

Breaking down the form (x^3 - y^3 = (x - y)(x^2 + xy + y^2)).

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Simplification of Fractions

Simplifying a fraction by factorising the numerator and denominator and cancelling common factors.

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Converting Recurring Decimals

A method to represent a recurring decimal as a fraction by multiplying by powers of 10 and subtracting.

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Perfect Squares

Numbers obtained when squaring an integer (e.g., 9 from 3^2).

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Perfect Cubes

Numbers obtained when cubing an integer (e.g., 27 from 3^3).

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Surd Comparison

If a and b are positive whole numbers, and a < b, then (\sqrt[n]{a} < \sqrt[n]{b}).

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Multiplying Two Binomials

Expanding ((ax + b)(cx + d)) results in (acx^2 + adx + bcx + bd).

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Binomial and Trinomial Product

To find the product of ((A + B)) and ((C + D + E)), use: [(A + B)(C + D + E) = A(C + D + E) + B(C + D + E).]

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Cancelling Common Factors

Simplify by dividing both the numerator and denominator by their greatest common factor.

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Division of Fractions

Rewrite division as multiplication by the reciprocal.

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Terminating Decimal

A decimal number that has a finite number of digits.

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Repeating Decimal

A decimal number that repeats the same digits or sequence of digits infinitely.

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Rounding Up

When the next digit is 5 or greater, increase the last digit of the required decimal place by one.

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Rounding Down

When the next digit is less than 5, leave the last digit of the required decimal place unchanged.

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Perfect Fourth Powers

Numbers obtained when an integer is raised to the power of 4, e.g., 16 from 2^4.

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Term with Coefficient

An expression with a numerical coefficient and variable.

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Converting Recurring Decimals into Fractions

The process of rewriting a recurring decimal as a fraction in its simplest form.

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Irrational Number Approximation

A method to approximate irrational numbers by truncating or rounding to a rational number.

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Factorise First

To simplify, apply factorization techniques (common factors, difference of squares, quadratic trinomials).

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Distribution

Expanding the product of expressions by distributing each term.

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Study Notes

The Real Number System

  • The real number system includes subsets of numbers commonly used in math.

  • Natural Numbers (N):

    • Positive integers starting from 1.
    • Symbol: ( N )
    • Set: ( {1, 2, 3, \ldots} )
  • Whole Numbers ((N_0)):

    • Includes natural numbers and zero.
    • Symbol: ( N_0 )
    • Set: ( {0, 1, 2, 3, \ldots} )
  • Integers (Z):

    • Includes whole numbers and their negative counterparts.
    • Symbol: ( Z )
    • Set: ( {\ldots, -3, -2, -1, 0, 1, 2, 3, \ldots} )
  • Rational Numbers (Q):

    • Numbers expressible as a fraction of two integers, where the denominator isn't zero.
    • Symbol: ( Q )
    • Examples: ( \frac{1}{2}, \frac{4}{5}, -\frac{3}{7}, 0.75, 0 )
  • Irrational Numbers (Q'):

    • Numbers not expressible as a simple fraction of two integers.
    • Decimal expansions are non-repeating and non-terminating.
    • Symbol: ( Q' )
    • Examples: ( \sqrt{2}, \pi, e )
  • Real Numbers (R):

    • Includes all rational and irrational numbers.
    • Symbol: ( R )
    • Examples: ( \sqrt{2}, -3, 4.5, \pi )

Non-Real or Imaginary Numbers

  • Imaginary Numbers: Numbers that have a negative square root.

    • Examples: ( \sqrt{-1}, \sqrt{-28}, \sqrt{-5} )
  • Hierarchy of number sets:

    • Real Numbers (( R )) include:
      • Rational Numbers (( Q )) which include:
        • Integers (( Z )) which include:
          • Whole Numbers (( N_0 )) which include:
            • Natural Numbers (( N ))
      • Irrational Numbers (( Q' ).

Rational Numbers (Q)

  • Rational Numbers (Q): Can be written in the form ( \tfrac{a}{b} ), where ( a ) and ( b ) are integers and ( b \neq 0 ).

Irrational Numbers (Q')

  • Irrational Numbers (Q'): Cannot be written as a fraction with integer numerator and denominator.

Decimal Numbers

  • Rational numbers include:
    • Terminating decimals
    • Repeating single digit decimals
    • Repeating pattern of multiple digits decimals

Converting Terminating Decimals into Rational Numbers

  • For a decimal number ( x ):
    • [ x = \text{integer part} + \frac{\text{first decimal digit}}{10} + \frac{\text{second decimal digit}}{100} + \frac{\text{third decimal digit}}{1000} + \ldots ]

Converting Recurring Decimals into Rational Numbers

  • For a recurring decimal ( x ):
    • Let ( x = \text{recurring decimal} ).
    • Multiply ( x ) by a power of 10 to align the recurring pattern after the decimal point.
    • Subtract the original equation from this new equation.
    • Solve for ( x ).

Key Points on Rational and Irrational Numbers

  • Rational numbers can be expressed as ( \frac{a}{b} ) with ( a, b \in \mathbb{Z} ) and ( b \neq 0 ).
  • Irrational numbers cannot be written as simple fractions and have non-repeating, non-terminating decimal expansions.
    • Decimal forms:
      • Rational if terminating or repeating
      • Irrational if non-terminating and non-repeating
  • Rounding off an irrational number converts it into a rational approximation.

Rounding Off Decimal Numbers

  • Steps to Round Off a Decimal Number:
    • Identify the required decimal place: Count the number of decimal places needed and mark the digit after this position.
    • Determine the rounding direction:
      • If the next digit is 5 or greater, round up the last digit of the required decimal place.
      • If the next digit is less than 5, leave the last digit of the required decimal place unchanged.
      • If the digit to be rounded up is 9, it becomes 0, and the preceding digit is rounded up by 1.

Key Points for Rounding

  • For ( x ), rounded to ( n ) decimal places:
    • Identify the ( n )-th decimal digit and the ( (n+1) )-th digit.
    • Apply rounding rules based on the value of the ( (n+1) )-th digit.
    • Adjust accordingly and present the rounded number.

Estimating Surds

  • Surds: The (n)-th root of a number that cannot be simplified to a rational number.
    • For example, (\sqrt{2}) and (\sqrt{6}) are surds, but (\sqrt{4}) is not because ( \sqrt{4} = 2 )
    • Surds are often in the form (\sqrt[n]{a}) where (a) is any positive number. For example, (\sqrt{7}) or (\sqrt{5})
    • For (n = 2), this is written as (\sqrt{a}) instead of (\sqrt[2]{a}).

Estimation Process for Surds

  • Identify Perfect Powers: Determine the nearest perfect squares or cubes (or higher powers) that surround the given surd.
    • Perfect Squares: Numbers obtained when an integer is squared (e.g., 9 from (3^2)).
    • Perfect Cubes: Numbers obtained when an integer is cubed (e.g., 27 from (3^3)).
  • Comparison:
    • If ( a ) and ( b ) are positive whole numbers, and ( a < b ), then ( \sqrt[n]{a} < \sqrt[n]{b} ).

Products

  • Term: A single mathematical entity.
  • Expression: A combination of terms.
  • Coefficient: The numerical factor in a term.
  • Exponent: The power to which a base is raised.
  • Base: The variable or number being raised to a power.
  • Constant: A term without a variable.
  • Variable: A symbol representing an unknown quantity.
  • Equation: A statement that two expressions are equal.
  • A monomial is an expression with one term. A binomial is an expression with two terms. A trinomial is an expression with three terms.

Multiplying Two Binomials

  • The general formula for multiplying two linear binomials ((ax + b)(cx + d)) is:
    • ((ax + b)(cx + d) = acx^2 + adx + bcx + bd)

Multiplying a Binomial and a Trinomial

  • Use the following:
    • ((A + B)(C + D + E) = A(C + D + E) + B(C + D + E))

Operations

  • Multiplying a Monomial and a Binomial:
    • [ a(x + y) = ax + ay ]
  • Multiplying Two Binomials:
    • [ (ax + b)(cx + d) = acx^2 + adx + bcx + bd ]
  • Multiplying a Binomial and a Trinomial:
    • [ (A + B)(C + D + E) = A(C + D + E) + B(C + D + E) ]

Factorisation

  • Factorisation: Breaking down an expression into simpler expressions (factors) that, when multiplied together, give the original expression.

Common Factors

  • Factorising by taking out a common factor: Identifying and extracting a factor common to all terms in the expression.

Difference of Two Squares

  • A difference of two squares can be factorised using the identity:
    • [ a^2 - b^2 = (a + b)(a - b) ]

Factorising by Grouping in Pairs

  • Factorising by grouping: Grouping terms with common factors and then factorising each group.

Factorising a Quadratic Trinomial

  • A quadratic trinomial of the form (ax^2 + bx + c) can be factorised by finding two binomials whose product is the original trinomial.

General Procedure for Factorising a Trinomial

  • Identify any common factors.
  • Write down two brackets with an (x) in each bracket:
    • [ (x\ \ ) (x\ \ ) ]
  • List the factors of (a) and (c).
  • Generate possible pairs of factors.
  • Expand the pairs to find the one that matches the middle term (bx).

Sum and Difference of Two Cubes

  • Sum of Two Cubes:
    • [ x^3 + y^3 = (x + y)(x^2 - xy + y^2) ]
  • Difference of Two Cubes:
    • [ x^3 - y^3 = (x - y)(x^2 + xy + y^2) ]
  • These identities can be used to factorise expressions involving the sum or difference of cubes.

Simplification of Fractions

Multiplication and Division of Fractions

  • ( \frac{a}{b} \times \frac{c}{d} = \frac{ac}{bd} ) where ( b \neq 0 ) and ( d \neq 0 )
  • ( \frac{a}{b} \div \frac{c}{d} = \frac{a}{b} \times \frac{d}{c} = \frac{ad}{bc} ) where ( b \neq 0 ), ( c \neq 0 ), and ( d \neq 0 )

Addition of Fractions

  • [ \frac{a}{b} + \frac{c}{b} = \frac{a + c}{b} \quad \text{where } b \neq 0 ]

Simplification of Algebraic Fractions

  • Factorise the numerator and the denominator: Apply factorisation techniques (common factors, difference of squares, quadratic trinomials).
  • Cancel common factors: Reduce the fraction by cancelling common factors in the numerator and denominator.

Steps for Simplification

  • Factorise the expression: Factorise both the numerator and the denominator to identify common factors.
  • Cancel the common factors: Simplify the fraction by cancelling the common factors in the numerator and denominator.

General Procedures for Simplifying Complex Fractions

  • Factorise all terms in the numerator and denominator.
  • Rewrite the division as multiplication by the reciprocal.
  • Combine fractions by finding a common denominator if necessary.
  • Simplify the resulting expression.

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