MATH100 Precalculus Lecture Notes
36 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the outcome when substituting $x = 0$ into the inequality $2x^2 - 3x + 1 ≤ 0$?

  • True, the inequality holds.
  • True, it equals zero.
  • False, it results in a negative value.
  • False, it yields a result greater than zero. (correct)

Which test point correctly supports the interval $(-1/2, 1)$ solving the inequality?

  • $x = 1$ results in a true statement.
  • $x = 0$ yields a false result.
  • $x = 1/2$ gives a true statement. (correct)
  • $x = -1/2$ produces a false outcome.

What does the tested point $x = 2$ reveal about the interval $(1, ext{∞})$?

  • It supports the interval by yielding a negative value.
  • It refutes the interval as it gives a positive value. (correct)
  • It confirms the interval by yielding true.
  • It provides no relevant information about the interval.

What is the correct solution set for the inequality $2x^2 - 3x + 1 ≤ 0$ based on tested intervals?

<p>(-1/2, 1] as a closed interval. (B)</p> Signup and view all the answers

In solving $2x^2 - 3x + 1 ≤ 0$, which conclusion can be drawn from testing $x = -1/2$?

<p>It yields a negative value supporting the interval. (C)</p> Signup and view all the answers

What defines the domain of a function?

<p>The set of all possible values of $x$ (B)</p> Signup and view all the answers

Which of the following statements is true regarding a function?

<p>A function must have a one-to-one relationship between $x$ and $y$ (C)</p> Signup and view all the answers

What happens in computing when a division by zero occurs?

<p>It can lead to system failures due to buffer overruns (B)</p> Signup and view all the answers

In the context of functions, what does the range represent?

<p>The set of all output values ($y$) when $x$ is in the domain (B)</p> Signup and view all the answers

Why is dividing by zero prohibited in mathematics?

<p>It results in infinity, which cannot be handled (C)</p> Signup and view all the answers

What is the domain of the function $g(x) = -3x^2 + 4x + 5$?

<p>All real numbers (C)</p> Signup and view all the answers

For the function $f(x) = \frac{x-4}{x+3}$, what value must be excluded from the domain?

<p>-3 (A)</p> Signup and view all the answers

What is the domain of the function $f(x) = \frac{x+1}{(x-3)(x+5)}$?

<p>All real numbers except 3 and -5 (C)</p> Signup and view all the answers

What is the domain of the function $f(x) = \frac{4}{x^2 - 9}$?

<p>All real numbers except 3 and -3 (A)</p> Signup and view all the answers

For the function $f(x) = \frac{x-1}{x^2 + 4x + 3}$, which values are excluded from the domain?

<p>-1 and -3 (D)</p> Signup and view all the answers

What is the domain of the function $f(x) = \frac{5}{x^2 + 9}$?

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

What values need to be excluded from the domain for the function $f(x) = \frac{x}{x-1}$?

<p>1 only (D)</p> Signup and view all the answers

From the graph of the function $f(x) = x + 3$, what is the domain?

<p>[–3, ∞) (C)</p> Signup and view all the answers

What is the domain of the function $f(x) = \frac{1}{x}$?

<p>All real numbers except 0 (D)</p> Signup and view all the answers

In the function $f(x) = x^2 + 1$, which of the following is true about its domain?

<p>It includes all real numbers (A)</p> Signup and view all the answers

What is the solution set for the inequality $3x - 2 + 3 \geq 11$?

<p>$x \in (-\infty, -2) \cup (\frac{10}{3}, \infty)$ (B)</p> Signup and view all the answers

Which of the following describes the equivalent form of the inequality $2x + 1 > 9$?

<p>$2x + 1 &lt; -9 ; OR ; 2x + 1 &gt; 9$ (D)</p> Signup and view all the answers

What does the Vertical Line Test assess regarding a graph?

<p>If the graph is a function (A)</p> Signup and view all the answers

For the case when $x < a$, where $a > 0$, what is the equivalent inequality?

<p>$-a &lt; x &lt; a$ (C)</p> Signup and view all the answers

What defines the set of rational numbers?

<p>All numbers that can be expressed as a fraction of two integers. (C)</p> Signup and view all the answers

What is a condition for a relation to be considered a function?

<p>Each input must correspond to exactly one output (B)</p> Signup and view all the answers

Identify the solution set for the inequality $2x - 4 > 8$.

<p>$x ∈ (6, ∞)$ (D)</p> Signup and view all the answers

Which statement is true regarding the inequality $x - 3 < 5$?

<p>$-5 &lt; x - 3 &lt; 5$ (B)</p> Signup and view all the answers

What is the solution for the inequality $2x + 1 < -9$?

<p>$x &lt; -5$ (B)</p> Signup and view all the answers

What is the solution set for the inequality $2x + 1 < -9$?

<p>$x &lt; -5$ (A)</p> Signup and view all the answers

What technique is used to solve the inequality $2x^2 - 3x + 1 ≤ 0$?

<p>Factoring the quadratic equation. (A)</p> Signup and view all the answers

In the context of absolute value inequalities, what does $x > a$ result in?

<p>$x &lt; -a$ or $x &gt; a$ (B)</p> Signup and view all the answers

When testing the intervals from the equation $2x^2 - 3x + 1 = 0$, what must be done first?

<p>Find the zeros and create intervals around them. (D)</p> Signup and view all the answers

Which of the following sets contains only integers?

<p>$Z = {..., -2, -1, 0, 1, 2, ...}$ (D)</p> Signup and view all the answers

Which statement is true about irrational numbers?

<p>They include numbers like π and e. (D)</p> Signup and view all the answers

What does the notation $x ∈ (−∞, −5)$ indicate?

<p>x is less than -5 and does not include -5. (A)</p> Signup and view all the answers

Flashcards

Domain of a function

The set of all possible input values (x-values) for which a function is defined.

Domain: Example 1

All real numbers (ℝ)

Domain: Example 2

All real numbers except -3 (ℝ - {-3})

Domain: Example 3

All real numbers except 3 and -5 (ℝ - {3, -5})

Signup and view all the flashcards

Domain: Example 4

All real numbers except 3 and -3 (ℝ - {3, -3})

Signup and view all the flashcards

Domain: Example 5

All real numbers except -1 and -3 (ℝ - {-1, -3})

Signup and view all the flashcards

Domain: Example 6

All real numbers (ℝ)

Signup and view all the flashcards

Domain: Example 7

All real numbers (ℝ)

Signup and view all the flashcards

Domain: Example 8

All real numbers except 1 (ℝ - {1})

Signup and view all the flashcards

Real Numbers

The set of all rational and irrational numbers.

Signup and view all the flashcards

Rational Numbers

Numbers that can be expressed as a fraction p/q, where p and q are integers and q is not zero.

Signup and view all the flashcards

Irrational Numbers

Numbers that cannot be expressed as a fraction; non-repeating, non-terminating decimals.

Signup and view all the flashcards

Integers

The set of whole numbers and their opposites, including zero.

Signup and view all the flashcards

Natural Numbers

The set of positive whole numbers.

Signup and view all the flashcards

Solving Inequalities

Finding the values of a variable that make an inequality true.

Signup and view all the flashcards

Inequality Symbol (>)

Represents 'greater than'.

Signup and view all the flashcards

Inequality Symbol (<)

Represents 'less than'.

Signup and view all the flashcards

Solving Inequality Example 1

2x - 4 > 8 ; Solution x > 6

Signup and view all the flashcards

Solving Inequality Example 2

2x + 1 < -9 ; Solution x < -5

Signup and view all the flashcards

Solving Inequalities

Finding the values of a variable that satisfy an inequality.

Signup and view all the flashcards

Interval Notation

A way to represent a range of values on a number line using brackets or parentheses.

Signup and view all the flashcards

Test Point

A value within an interval used to determine if the interval satisfies the inequality.

Signup and view all the flashcards

Inequality 2x^2 - 3x + 1 ≤ 0

A quadratic inequality expressing a condition on the variable x.

Signup and view all the flashcards

Solution Interval [1/2, 1]

The range of values for x that satisfy the quadratic inequality 2x^2 - 3x + 1 ≤ 0.

Signup and view all the flashcards

Absolute Value Inequality Case 1

If |x| < a, then -a < x < a.

Signup and view all the flashcards

Absolute Value Inequality Case 2

If |x| > a, then x < -a or x > a.

Signup and view all the flashcards

Solving |x - 3| < 5

This inequality is solved by finding the values of x that are between -2 and 8, inclusive, i.e., -2 < x < 8.

Signup and view all the flashcards

Solving |2x + 1| > 9

This inequality breaks into two parts: 2x + 1 < -9 or 2x + 1 > 9. Solutions include all x < -5 or x > 4.

Signup and view all the flashcards

Solving |3x - 2| + 3 ≥ 11

Isolate the absolute value, then split into two inequalities: 3x - 2 ≥ 8 or 3x - 2 ≤ -8. Solve for x.

Signup and view all the flashcards

Function Definition

A relation where each input value (x) is associated with exactly one output value (y).

Signup and view all the flashcards

Vertical Line Test

A graph represents a function if no vertical line intersects the graph more than once.

Signup and view all the flashcards

Function example

y = x^2

Signup and view all the flashcards

Function

A relation where each input (x-value) has only one output (y-value).

Signup and view all the flashcards

Not a Function

A relation where a single input (x-value) maps to multiple outputs (y-values).

Signup and view all the flashcards

Domain

The set of all possible input values (x-values) in a function.

Signup and view all the flashcards

Range

The set of all possible output values (y-values) in a function.

Signup and view all the flashcards

Division by Zero

An undefined mathematical operation; it is impossible to divide any number by zero.

Signup and view all the flashcards

Undefined Value

A value that is not assigned a meaning or a numerical outcome.

Signup and view all the flashcards

Study Notes

MATH100 Precalculus - Lecture Notes

  • Lecture #1: Covers introduction to functions, solving inequalities, and domain and range of a function.

Real Numbers

  • Real numbers are the combination of rational and irrational numbers.
  • Rational numbers (Q): Numbers that can be expressed as a fraction p/q, where p and q are integers and q ≠ 0. Examples: -1/2, 0, 3, 2.5.
  • Irrational numbers (Q'): Numbers that cannot be expressed as a fraction of two integers. Examples: π, √2, √3
  • Integers (Z): Whole numbers, including zero and negative numbers. Examples: ..., -3, -2, -1, 0, 1, 2, 3,...
  • Natural numbers (N): Positive whole numbers. Examples: 1, 2, 3,...

Solving Inequalities: Examples

  • Example 1: Solving 2x - 4 > 8 results in x > 6. The solution set is x ∈ (6, ∞).
  • Example 2: Solving 2x + 1 < -9 results in x < -5. The solution set is x ∈ (-∞, -5).
  • Example 3: Solving 1 - 2x < 9 (needs the solution)
  • Example 4: Solving 2x² - 3x + 1 ≤ 0 results in the interval [1/2, 1].
    • Finding zeros of 2x² - 3x + 1 = 0: x = 1/2 and x = 1.
    • Testing intervals to determine the solution set to the inequality.

Absolute Value Inequalities: Examples

  • Case 1: |x| < a is equivalent to −a < x < a
  • Case 2: |x| > a is equivalent to x < −a or x > a
  • Example 1: Solving |x − 3| < 5 results in −2 < x < 8. The solution set is x ∈ (−2, 8).
  • Example 2: Solving |2x + 1| > 9 results in x < −5 or x > 4. The solution set is x ∈ (−∞, −5) ∪ (4, ∞).
  • Example 3: Solving |3x − 2| + 3 ≥ 11 results in x ≥ 10/3 or x ≤ −2/3. The solution set is x ∈ (−∞, −2/3] ∪ [10/3, ∞).

Function Definition

  • A function is a relation that assigns each input value to exactly one output value.
  • The notation is y = f(x), where x is the input, y is the output, and f is the function.
  • Examples include y = x², y = √x.
  • Function examples are plotted (parabolas, sine waves, circles)

The Vertical Line Test

  • A graph represents a function if no vertical line intersects the graph at more than one point.

Domain and Range of a Function

  • Domain: The set of all possible input values (x-values) for which the function is defined.

  • Range: The set of all possible output values (y-values) that the function can produce.

  • Examples:

    • Example 1: g(x) = −3x² + 4x + 5 has a domain of all real numbers.
    • Example 2: f(x) = (x-4)/(x+3) has a domain of all real numbers except x = -3.
    • Example 3: f(x) = (x+1)/((x-3)(x+5)) has a domain of all real numbers except x = 3 and x = -5.
    • Example 4: f(x) = 4/(x²−9) has a domain of all real numbers except x = 3 and x = −3
    • Example 5: f(x) = (x-1)/(x² + 4x + 3) has a domain of all real numbers except x = −1 and x=−3
  • Finding domain and range from graphs: visual analysis

  • Why aren't we allowed to divide by zero? A historical example of a real-world problem stemming from attempting to divide by zero in computer code.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

Description

This quiz covers key concepts from MATH100 Precalculus, including an introduction to functions, real numbers, and methods for solving inequalities. Participants will explore types of numbers such as rational, irrational, integers, and natural numbers, along with practical examples of solving inequalities. Prepare to test your knowledge on these foundational topics!

More Like This

Use Quizgecko on...
Browser
Browser