Podcast
Questions and Answers
Which of the following collections can be definitively considered a set?
Which of the following collections can be definitively considered a set?
- All prime numbers less than 20. (correct)
- A selection of the best movies of the year, chosen by a critic.
- The most talented musicians in a city.
- The top five students in a class known for high academic variance.
How would the set containing the solutions to the equation $x^2 + 2x + 1 = 0$ be represented in roster form?
How would the set containing the solutions to the equation $x^2 + 2x + 1 = 0$ be represented in roster form?
- {-1} (correct)
- {-1, -1}
- {1, 1}
- {1}
Which of the sets below is equivalent to the set A = {x | x ∈ N and x is a multiple of 3 less than 15}?
Which of the sets below is equivalent to the set A = {x | x ∈ N and x is a multiple of 3 less than 15}?
- {1, 3, 6, 9, 12}
- {3, 6, 9, 12} (correct)
- {3, 6, 9, 12, 15}
- {0, 3, 6, 9, 12}
If set A = {x | x is a vowel in the English alphabet}, which of the following correctly expresses that the letter 'b' does not belong to set A?
If set A = {x | x is a vowel in the English alphabet}, which of the following correctly expresses that the letter 'b' does not belong to set A?
Which of the following sets represents an empty set?
Which of the following sets represents an empty set?
Given set A = {x : x ∈ N and $x^2 - 5x + 6 = 0$}, determine whether set A is finite or infinite.
Given set A = {x : x ∈ N and $x^2 - 5x + 6 = 0$}, determine whether set A is finite or infinite.
Determine if the following sets A and B are equal: A = {x : x ∈ N and $(x-2)(x+3) = 0$}, B = {-3, 2}.
Determine if the following sets A and B are equal: A = {x : x ∈ N and $(x-2)(x+3) = 0$}, B = {-3, 2}.
If A = {1, 2, 3} and B = {1, 2, 3, 4, 5}, is A a subset of B?
If A = {1, 2, 3} and B = {1, 2, 3, 4, 5}, is A a subset of B?
Given that set A = {a, b} and set B = {a, b, c}, which of the following statements is correct regarding the relationship between A and B?
Given that set A = {a, b} and set B = {a, b, c}, which of the following statements is correct regarding the relationship between A and B?
Which of the following is true regarding the empty set ($\emptyset$)?
Which of the following is true regarding the empty set ($\emptyset$)?
Identify which of the following sets is a singleton set.
Identify which of the following sets is a singleton set.
Which interval notation correctly represents the set of all real numbers greater than -3 and less than or equal to 5?
Which interval notation correctly represents the set of all real numbers greater than -3 and less than or equal to 5?
How many subsets can be formed from the set A = {1, 2, 3, 4}?
How many subsets can be formed from the set A = {1, 2, 3, 4}?
Given A = {1, 2, 3} and B = {3, 4, 5}, which Venn diagram correctly shows the relationship between sets A and B?
Given A = {1, 2, 3} and B = {3, 4, 5}, which Venn diagram correctly shows the relationship between sets A and B?
If U is considered the universal set, what is the result of $U \cup A$ for any set A?
If U is considered the universal set, what is the result of $U \cup A$ for any set A?
If A = {1, 2, 3} and B = {3, 4, 5}, what is $A \cup B$?
If A = {1, 2, 3} and B = {3, 4, 5}, what is $A \cup B$?
Given A = {1, 2, 3}, what is $A \cup \emptyset$?
Given A = {1, 2, 3}, what is $A \cup \emptyset$?
According to the commutative law of sets, which expression is equivalent to $A \cup B$?
According to the commutative law of sets, which expression is equivalent to $A \cup B$?
If sets A, B, and C are given, which of the following expressions represents the associative law for the union of sets?
If sets A, B, and C are given, which of the following expressions represents the associative law for the union of sets?
Which of the following represents the identity law for the union of sets?
Which of the following represents the identity law for the union of sets?
What is the result of A ∪ A , according to the idempotent law?
What is the result of A ∪ A , according to the idempotent law?
Given a universal set U and any set A, what does $U \cup A$ simplify to?
Given a universal set U and any set A, what does $U \cup A$ simplify to?
If A = {1, 2, 3, 4, 5} and B = {4, 5, 6, 7}, what is A ∩ B?
If A = {1, 2, 3, 4, 5} and B = {4, 5, 6, 7}, what is A ∩ B?
According to the Commutative Law, is A ∩ B equivalent to B ∩ A?
According to the Commutative Law, is A ∩ B equivalent to B ∩ A?
According to the Associative Law, which of the following is equivalent to (A ∩ B) ∩ C?
According to the Associative Law, which of the following is equivalent to (A ∩ B) ∩ C?
What is ∅ ∩ A equal to for any set A?
What is ∅ ∩ A equal to for any set A?
Given that U is the universal set and A is any set, what does U ∩ A equal?
Given that U is the universal set and A is any set, what does U ∩ A equal?
According to the Idempotent Law, what is the simplified form of A ∩ A?
According to the Idempotent Law, what is the simplified form of A ∩ A?
How can the Distributive Law of intersection over union be expressed?
How can the Distributive Law of intersection over union be expressed?
What is the difference A - B defined as?
What is the difference A - B defined as?
If A = {1, 2, 3, 4} and B = {3, 4, 5, 6}, what does A - B equal?
If A = {1, 2, 3, 4} and B = {3, 4, 5, 6}, what does A - B equal?
Given sets A and B, which expression is equivalent to A - (A ∩ B)?
Given sets A and B, which expression is equivalent to A - (A ∩ B)?
If A = B, what is A - B?
If A = B, what is A - B?
If B = ∅, what is A - B for any set A?
If B = ∅, what is A - B for any set A?
Which of the following is true if A is a subset of B?
Which of the following is true if A is a subset of B?
What is A – U (where U is the universal set)?
What is A – U (where U is the universal set)?
When are the sets A – B, A ∩ B, and B – A considered mutually disjoint?
When are the sets A – B, A ∩ B, and B – A considered mutually disjoint?
Let U be a universal set, and A be a subset of U. Which of the following represents the complement of A?
Let U be a universal set, and A be a subset of U. Which of the following represents the complement of A?
Given a set A, what is (A')'?
Given a set A, what is (A')'?
Which of the following expressions is equivalent to the universal set U?
Which of the following expressions is equivalent to the universal set U?
According to De Morgan's Laws, what is the complement of A ∪ B ?
According to De Morgan's Laws, what is the complement of A ∪ B ?
According to De Morgan's Laws, which expression is equivalent to $(A ∩ B)'$?
According to De Morgan's Laws, which expression is equivalent to $(A ∩ B)'$?
If A and B are finite sets such that A ∩ B = ∅, and n(A) = 5 and n(B) = 3, what is n(A ∪ B)?
If A and B are finite sets such that A ∩ B = ∅, and n(A) = 5 and n(B) = 3, what is n(A ∪ B)?
Given sets A and B are finite such that A ∩ B ≠ ∅, and n(A) = 10, n(B) = 8, and n(A ∪ B) = 12, what is n(A ∩ B)?
Given sets A and B are finite such that A ∩ B ≠ ∅, and n(A) = 10, n(B) = 8, and n(A ∪ B) = 12, what is n(A ∩ B)?
Flashcards
What is a set?
What is a set?
A well-defined collection of objects.
What does x ∈ S mean?
What does x ∈ S mean?
x belongs to S.
What does x ∉ S mean?
What does x ∉ S mean?
x does not belong to S.
What is Roster form?
What is Roster form?
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What is Set-builder form?
What is Set-builder form?
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What is an empty set?
What is an empty set?
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What is a finite set?
What is a finite set?
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What are Equal sets?
What are Equal sets?
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What is A ⊆ B?
What is A ⊆ B?
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Empty set as a subset?
Empty set as a subset?
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What is singleton set?
What is singleton set?
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What is Open interval (a, b)?
What is Open interval (a, b)?
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What is Closed interval [a, b]?
What is Closed interval [a, b]?
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What is a power set?
What is a power set?
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What is a Universal set?
What is a Universal set?
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What is the Union of sets?
What is the Union of sets?
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What is Commutative law in union of sets?
What is Commutative law in union of sets?
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What is Associative law in union of sets?
What is Associative law in union of sets?
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What is The identity of Ø in union of sets?
What is The identity of Ø in union of sets?
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What is Idempotent Law in union of sets?
What is Idempotent Law in union of sets?
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What is Commutative law in intersection of sets?
What is Commutative law in intersection of sets?
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What is Associative law in intersection of sets?
What is Associative law in intersection of sets?
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What is The identity of p in intersection of sets?
What is The identity of p in intersection of sets?
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What is The identity of U in intersection of sets?
What is The identity of U in intersection of sets?
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What is Distributive Law of ∩ on ∪?
What is Distributive Law of ∩ on ∪?
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What is the Difference between the sets?
What is the Difference between the sets?
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What is Complement of a set?
What is Complement of a set?
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What is Properties of complement of a set?
What is Properties of complement of a set?
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What is Cartesian product of sets?
What is Cartesian product of sets?
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What is a Relation?
What is a Relation?
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What is the domain of the relation R?
What is the domain of the relation R?
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What is the Range?
What is the Range?
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What is a function?
What is a function?
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What is Identity function?
What is Identity function?
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What is Constant function?
What is Constant function?
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What is polynomial function?
What is polynomial function?
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What is Modulus Function?
What is Modulus Function?
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Study Notes
Chapter 1: Sets
- A set can be defined as a well-defined collection of objects
- An example of set: the collection of all rational numbers less than 10
- An example of non-set: the collection of all brilliant students in a class
- Sets are usually denoted by capital letters A, B, S,
- Elements of a set are usually denoted by small letters a, b, t, u
- If x is an element of a set S, then “x belongs to S” which is written as x ∈ S
- If y is not an element of a set S, then “y does not belong to S” which is written as y ∉ S
Methods for representing a set
- Roster or tabular form lists all the elements of a set
- Elements are separated by commas and enclosed within braces { }
- Order is immaterial
- Elements are not repeated
- Example: The set of letters forming the word ‘TEST' is {T, E, S}.
- Set-builder form means all the elements of a set possess a single common property
- No element outside the set possesses the property
- Example: The set {2, –2} can be written in the set-builder form as {x : x is an integer and x² - 4 = 0}.
Types of sets
- An empty set contains no element
- Empty sets are called a null set or a void set.
- Denoted by the symbol p or { }
- Example: The set {x : x ∈ N, x is an even number and 8 < x < 10} is an empty set
- A finite set is empty or consists of a definite number of elements
- An infinite set is not a finite
- Example: The set {x : x ∈ N and x is a square number} is an infinite set
- Example: The set {x : x ∈ N and x2 - 2x – 3 = 0} is a finite set as it is equal to {−1,3}
- Infinite sets cannot be described in the roster form
- The set of rational numbers cannot be described in this form
- Elements of this set do not follow any particular pattern
Equal and Unequal Sets
- Two sets A and B are equal if they have exactly the same elements
- Equal sets are written A = B
- Unequal sets are written A ≠ B
- Example: The sets A = {x: x ∈ N and (x-1)(x + 4) = 0} and B = {–4, 1} are equal sets
- Order of element does not matter
- Example: The sets A = {E, L, E, M, E, N, T, S} and B = {E, L, M, N, T, S} are equal since each element of A is in B, and vice-versa
- A set does not change if one or more elements of the set are repeated
Subsets
- Set A is a subset of set B if every element of A is also an element of B
- Written as A ⊂ B
- A ⊂ B if a ∈ A⇒a∈B
- A ⊂ B and B ⊂ A ⇔ A = B
- An empty set is a subset of every set
- Every set is a subset of itself
- If A ⊂ B and A ≠ B, then A is a proper subset of B
- B is called a superset of A
Singleton Set
- All sets with one element are singleton sets.
- Example: A = {-17} is a singleton set
Intervals
- Intervals are subsets of R
- Let a, b ∈ R and a < b
- {y : a <y<b} is an open interval and is denoted by (a, b)
- In the open interval (a, b), all the points between a and b belong to the open interval (a, b)
- a, b themselves do not belong to this interval
- {y : a ≤ y ≤ b} is a closed interval and is denoted by [a, b]
- In this interval, all the points between a and b as well as the points a and b are included
- [a, b) = {y : a ≤ y <b} is an open interval from a to b, including a, but excluding b
- (a, b] = {y : a < y ≤b} is an open interval from a to b, including b, but excluding a
Power set
- The collection of all subsets of a set A is called the power set of A
- Denoted by P(A)
- If A is a set with n(A) = m, then n[P(A)] = 2m
Venn diagrams
- Relationships between sets are represented by diagrams known as Venn diagrams
- A universal set is the super set of all sets under consideration
- Denoted by U
Union of sets
- The union of two sets A and B is the set which contains all those elements which are only in A, only in B and in both A and B
- Denoted by ‘A ∪ B’
- A∪ B = {x : x ∈ A or x ∈ B}
Properties of union of sets
- A ∪ B = B ∪ A (Commutative Law)
- (A∪B)∪C = A∪(B∪C) (Associative Law)
- A ∪ ø = A (ø is the identity of )
- A ∪ A = A (Idempotent Law)
- U ∪ A=U (Law of U)
Intersection of sets
- The intersection of two sets A and B is the set of all those elements which belong to both A and B
- Denoted by ‘A ∩ Β’
- A∩B={x:x∈ A and x ∈ B}
Properties of intersection of sets
- A ∩ B = B ∩ A (Commutative Law)
- (A∩B)∩C = A∩(B∩C) (Associative Law)
- ø ∩ A = ø (Law of ø)
- U ∩ A = A (Law of U)
- A ∩ A = A( Idempotent Law)
- A ∩(B∪C)=(A∩B)∪(A∩C) (Distributive law of ∩ on ∪)
- A ∪ (B∩C) = (A ∪ B)∩(A ∪ C)
Difference of sets
- The difference between the sets A and B (i.e., A – B, in this order) is the set of the elements which belong to A, but not to B
- A − B = {x: x ∈ A and x ∉ B}
Properties of operation of difference of sets
- A − B =A − (A ∩ B)
- For A ≠ B, A - B ≠ B - A
- For A = B, A − B = B − A = φ
- For B = φ, A – B = A and B − A = ø
- A – U = ø
- For A ⊂ B, A – B = ø, for this reason, A – U = ø
- The sets A – B, A ∩ B and B – A are mutually disjoint sets
- Any intersection of these two sets is a null set
Complement of a set
- If U is a universal set and A is a subset of U, then the complements of A are denoted by the set A'
- This is the set of all element of U which are not the elements of A
- A' = {x : x ∈U and x ∉ A} =U-A
- A' is also the subset of U
Properties of complement of a set
- (A')' = A
- A∪A'=U
- A∩ A' = ø
- φ' = U and U' = φ
De Morgan's laws
- For any sets A and B, (A∪B)' = A' ∩ B' (A∩B)' = A' ∪ B'
Finite Sets
- If A and B are finite sets, such that A ∩ B = 4, then n(A∪B) = n(A)+n(B)
- If A and B are finite sets, such that A∩B ≠ ¢, then, n(A∪B) = n(A)+n(B)-n(A∩B)
- If A, B and C are finite sets, then n(A∪B∪C)=n(A)+n(B)+n(C)-n(A∩B)-n(B∩C)-n(A∩C)+n(A∩B∩C)
Chapter 2: Relations and Functions
- A Cartesian product of sets are constructed when provided with two non-empty sets P and Q
- The Cartesian product of P × Q is the set of all ordered pairs of elements from P and Q
- P × Q = {(p,q) : p∈ P and p∈Q}
- If either P or Q is a null set, then P × Q will also be a null set
- P × Q=¢
- In general, if A is any set, then A × ¢ = ¢
- Two ordered pairs are equal if and only if the corresponding first elements are equal and the second elements are also equal
- if (a, b) = (x, y), then a = x and b = y
- For any two sets A and B, A×B≠B×A
- If n(A) = p, n(B) = q, then n(A × B) = pq
- If A and B are non-empty sets and either A or B is an infinite set, then so is the case with A×B
- A×A×A = {(a,b,c): a,b,c ∈ A}
- Here, (a, b, c) is called an ordered triplet
Relation
- A relation R from a set A to a set B is a subset of the Cartesian product A × B
- Obtained by describing a relationship between the first element x and the second element y of the ordered pairs (x, y) in A × B
- The image of an element x under a relation R is y, where (x, y) ∈ R
- The set of all the first elements of the ordered pairs in a relation R from a set A to a set B is called the domain of the relation R
- The set of all the second elements in a relation R from a set A to a set B is called the range of the relation R
- The whole set B is called the co-domain of the relation R
- The total number of relations that can be defined from a set A to a set B is the number of possible subsets of A × B
- If n(A) = p and n(B) = q, then n(A × B) = pq and the total number of relations is 2pq
Functions
- A relation f from a set A to a set B is a function if every element of set A has one and only one image in set B
- A function f is a relation from a non-empty set A to another non-empty set B, such that the domain of f is A and no two distinct ordered pairs in f have the same first element
- The function f from A to B is denoted by f : A→ B
- A is the domain and B is the co-domain of f
- If f is a function from A to B and (a, b) ∈ f, then f (a) = b, where b is called the image of a under f, and a is called the pre-image of b under f
- A function having either R (real numbers) or one of its subsets as its range is called a real-valued function
- If its domain is also either R or a subset of R, it is called a real function
Types of functions
- Identity function: The function f: R → R defined by y = f(x) = x, for each x ∈ R, is called the identity function
- R is the domain and range of f
- Constant function: The function f: R → R defined by y = f (x) = c, for each x ∈ R, where c is a constant, is a constant function
- The domain of f is R and its range is {c}
- Polynomial function: A function f: R → R is said to be a polynomial function if for each x ∈ R, y = f(x) = a₀ +a₁x+.......+aₙxⁿ, where n is a non-negative integer and a₀,a₁........aₙ∈R
- Rational function: The functions of the type f(x)/g(x), where f(x) and g(x) are polynomial functions of x defined in a domain and where g(x) ≠ 0, are called rational functions
- Modulus function: The function f: R → R defined by f(x) = |x|, for each x ∈ R, is called the modulus function
- f(x) = x, x ≥0
- f(x) = -x, x < 0
- Signum function: The function f: R → R defined by f(x) = 1, if x>0 f(x) = 0, if x = 0 f(x) = −1, if x < 0
- Has a domain of R and its range is the set {−1, 0, 1}
- Greatest Integer function: The function f: R → R defined by f(x) = [x], x ∈ R, assuming the value of the greatest integer less than or equal to x, is called the greatest integer function
- Linear function: The function f defined by f (x) = mx +c, for x ∈ R, where m and c are constants, is called the linear function
- R is the domain and range of f
Algebra of functions
- For functions f: X → R and g: X → R, we define (f+g): X → R by (f + g)(x) = f (x)+g(x), x ∈ X (f-g): X → R by (f-g)(x) = f (x)−g(x), x ∈ X (fg): X → R by (fg)(x) = f (x).g(x), x ∈ X (af): X → R by (af)(x)=af(x), x ∈ X and a is a real number g : X → R by g(x) = f(x) , x ∈ X and g(x) ≠ 0 f(x)/
Chapter 3: Trigonometric Functions
-
Find the relationship between an angle and the length of a side
-
Consider a circle of radius r having an arc of length l that subtends an angle ofradians, where l = re
Relations Between Radian and Degree Measure
- Radian measure = π/180 × Degree measure.
- one sixtieth of a degree is called a minute, written as 1'
- one sixtieth of a minute is called a second, written as1"
- 1° = 60' and 1' = 60"
Domain and range of trigonometric functions
Trigonometric function | Domain | Range |
---|---|---|
sin x | R | [-1,1] |
cos x | R | [-1,1] |
tan x | R-{x:x=(2n+1)π/2, n∈Z} | R |
cot x | R-{x:x=nπ, n∈Z | R |
sec x | R-{x:x=(2n+1)π/2, n∈Z} | R - [-1,1] |
cosec x | R - {x:x = nπ, n∈Z | R - [-1,1] |
Signs of Trigonometric Functions in Different Quadrants
Trigonometric function | Quadrant-I | Quadrant -II | Quadrant III | Quadran-IV |
---|---|---|---|---|
sin x | +ve | +ve | -ve | -ve |
cos x | +ve | -ve | -ve | +ve |
tan x | +ve | -ve | +ve | -ve |
cot x | +ve | -ve | +ve | -ve |
Trigonometric identities
1 • cosec x = sin x 1 • sec x = COS X SinX • tan x = COS X 1 COS X • cot x = = tanx SIN X • Cos²x+Sin²X = 1 • 1+tan2 x= sec2 X • 1+CoT2 X = CoSEC 2x
Trigonometric ratios of allied angles
- sin (-x) = - sin x
- cos (-x) = cos x
- cos(π/2 -x)= sin x
- sin(π/2 - x) = cos x
- cos(π/2+x)= -sin x
- sin(π/2 + x)= cos x
- cos(π-x) = - cos x
- sin(π - x) = sin x
- cos(n+x)= - cos x
- sin(n+x) = -sinx
- cos(2n-x) = cos x
- sin(2n-x) = -sin x
- cos(2nn+x) = cosx, n ∈ Z
- sin(2n + x) = sinx, n ∈ Z
Sum and difference of two angles
• sin (x + y) = sin x cos y + cos x sin y • cos (x + y) = cos x cos y - sin x sin y • sin (x - y) = sin x cos y - cos x sin y • cos (x - y) = cos x cos y + sin x sin y -If none of the angles x, y and (x + y) is an odd multiple of π/2 then,
• tan(x + y) = tan x + tan y /1 - tan x tan y • cot(x + y) = cot x cot y - 1 / cot y + cot x -If none of the angles x, y and (x ± y) is a multiple of π, then • tan(x - y) = cot x cot y + 1/cot y - cot x
-Trigonometric ratios of multiple angles 1-tan²x/1+tan²x
- cos 2x = cos²x - sin²x = 2 cos²x - 1 = 1 - 2sin² x = 2tanx/1+tan²x
- sin 2x = 2 sin x cos x = 2 tanx / 1 - tan² x
- tan 2x =
- sin 3x = 3 sin x – 4 sin³ x
- cos 3x = 4 cos³x - 3 cos x -tan 3x = 3 tan x - tan³ x / 1 - 3 tan² x
Some more trigonometric identities
x + y/2 cosx - y/2
- sinx + siny = 2cos -cosx + cosy = -2sin x + y/2 sin - y/2 -sinx - siny = 2sin x + y/2 cosx - y/2
- cosx - cosy = 2sin x + y/2 sinx - y/2 cos + cos (x - y)
- 2 cos x cosy = cos (x + y) +
- 2 sin x sin y = cos (x + y) – cos (x - y)
- 2 sin x cos y = sin (x + y) + sin (x - y)
- 2 cos x sin y = sin (x + y) – sin (x - y)
General solutions of trigonometric equations
+nx = 0 ⇒ x = nπ, where ∈ Z -sin +cosx = 0 ⇒ x = (2n+1)π/2 where n ∈ Z +sin x = sin y ⇒ x = nπ+(−1)ⁿy, where ,n ∈ Z +cos x = cos y ⇒ x = 2nn #+y, where n ∈ Z +tan x = tan y ⇒ x = nπ + y, where n ∈ Z
Chapter 4: Principle of Mathematical Induction
- There are some mathematical statements or results that are formulated in terms of n, where n is a positive integer.
- To prove such statements, the well-suited principle that is used, based on the specific technique, is known as the principle of mathematical induction.
- To prove a given statement in terms of n, we assume the statement to be P(n).
- Thereafter, we examine the correctness of the statement for n = 1 i.e., for P(1) to be true.
- Then, assuming that the statement is true for n = k, where k is a positive integer, we prove that the statement is true for n = k + 1 i.e., the truth of P(k) implies the truth of P(k + 1).
- Then, we say that P(n) is true for all natural numbers n.
Chapter 5: Complex Numbers and Quadratic Equations
- A number of the form a + ib, where a and b are real numbers and i = √–1, is defined as a complex number.
- For the complex numbers z = a + ib, a is called the real part (denoted by Re z) and b is called the imaginary part (denoted by Im z) of the complex number z.
- Two complex numbers z₁ = a + ib and z₂ = c + id are equal if a = c and b = d.
Addition of complex numbers
- Let z₁ = a + ib and z₂ = c + id be any two complex numbers. The sum is defined as z₁ + z₂ = (a + c) + i (b + d).
Properties of addition of complex numbers
- (i) Closure law: Sum of two complex numbers is also a complex number.
- (ii) Commutative law: For two complex numbers z₁ and z₂, z₁ + z₂ = z₂ + z₁
- (iii) Associative law: For any three complex numbers z₁, z₂ and z₃, (z₁ + z₂) + z₃ = z₁ + (z₂ + z₃)
- (iv) Existence of additive identity: There exists a complex number 0 + i0 (denoted by 0), called the additive identity or zero complex number, such that for every complex number z, z + 0 = z
- (v) Existence of additive inverse: For every complex number z = a + ib, there exists a complex number –a + i(−b) [denoted by -z], called the additive inverse or negative of z, such that z + (−z) = 0
- Given any two complex numbers z₁ and z₂, the difference z₁ – z₂ is defined as z₁ - z₂ = z₁ + (-z₂)
Multiplication of complex numbers
- For two complex numbers z₁ and z₂, such that z₁ = a + ib and z₂ = c + id, the multiplication is defined as z₁ z₂ = (ac – bd) + i(ad + bc).
Properties of multiplication of complex numbers
- Closure law The product of two complex numbers is also a complex number.
- Commutative law For any two complex numbers z₁ and z₂, z₁z₂ = z₂z₁.
- Associative law For any three complex numbers z₁, z₂ and z₃, (z₁z₂) z₃ = z₁ (z₂z₃)
- Existence of multiplicative identity There exist a complex number 1 + i 0 (denoted as 1), called the multiplicative identity, such that for every complex numbers z, z.1 = z
Existence of multiplicative inverse: For every non-zero complex number z a + ib (a 0,b 0), we have the complex number a+-ba²+b²√ a²+b²= a²+b² + i( a²+b² ) a+b2 (denoted by 1/z or z ⁻¹), called the multiplicative inverse of z, such that z. 1/z =1 Distributive law: For any three complex numbers z₁, z₂ and z₃,z₁ (z₂ + z₃) = z₁z₂ + z₁z₃ (z₁ +z₂) z₃ = z₁z₃+ z₂z₃ Given any two complex number z₁ and z₂, where z₂ 0, the quotient z₁/ z₂ is defined as
- z₁/ z₂ * =0 (1/ z₂)
Powers of i
For any integer k, i⁴ᵏ = 1, i⁴ᵏ⁺¹ = i, i⁴ᵏ⁺² = −1, i⁴ᵏ⁺³ = −i
If a and b are negative real numbers, then √a × √b √ab.
- Identities for complex numbers* For two complex numbers z₁ and z₂.
- (z₁ + z₂)² = z₁² +2z₁z₂ + z₂²
- (z₁- z₂)² = z₁² -2z₁z₂ + z₂²
- z₁² - z₂² = (z₁+ z₂)( z₁ - z₂)
- (z₁ + z₂)^3 = z₁^3 +3z₂z₂ +3z₁z₂²+ z₂^3 (z₁- z₂)^3 = z₁^3 -3z₂z₂ +3z₁z₂² -z₂^3
Modulus and conjugate of complex numbers
- The modulus of a complex number z = a + ib, is denoted by/z/, and is defined as the nonnegative real number √a² + b², i.e., √a²+b².
- The conjugate of a complex number z = a + ib, is denoted by Z, and is defined as the complex number a ib, i.e., z =a-ib.
Properties of modulus and conjugate of complex numbers
For any three complex numbers z, z₁, z₂,
- z₁ z = /z/² or z.z =z/=2 1
- /z. z ² /-/z1/ . /z2/ /, provided /z₂/0 z
- z*₁_ =/z₁/= √₂ √₂
- √z₁z₂ ̅ =√z₁/√z₂ √z₁=/zī
The polar form of the complex number z = x + iy, is √ x² + y² (modulus of z) and cos0 = x/_*/2, i.e., √. .sin √ z= x-iy = re0+√ π
Is such that - <0 < n is called the principle arguments z.
Solution for the given equation
a≠ 0 is called solutions of quadratic equations by x="b-b+4ac/2e A polynomial equation of degree n has a root.
Chapter 6: Linear and in equalities.
- In linear qualities only x10 qualities in 2 variable.
-
Any set of value of x which it a member of solution is of lineal of qualities,
-
Solving qualities Algebricolys: + Equal number added to side of qualities without effecting sin. + When both sides and multiply by - value, is side reverse.
+ Graphical representation:-
-
Represent x < a on number line, incide number dark line to the side from.
-
Representing x 1 <a, dark number line to the side from.
graphical solution of linear qualities and 2 variable
- Solution solution reason system and system.
- Identify to have plant equation.
- (1A) < O are green x = 2ª - a √ac-b ² /a . is called form of equation
Chapter 7: Permutations and combination
- Events found fundamental princible = m x h/ is m different way found h.
- Arrg.definite = permutations/
Notation
- Factorial notation represented product notation numbers L/E - Nx/x/(1)/0
Number of permutation
- Repetition allowed
- Repetition - = p
Distinct permulations
- P elements kind of distinct n elements = n
- N Ob. - distinct types = equation A distinct selection is = arrangement- A number = combination
Combination, Equation = ⁰ C
propert
- Cr
ch8 binomial thereal
- Pascal triangle
- Expansion = N c a n * 150
Ch-9 sequence and series
A sequence : arrangements numbers = to number of some role, and function
- Series 1/2/3/ equation = 123/12/3/ is to be Geometric progressions = Same throughout = to be .
- Series progression same throught formula/arithmetic progressions.
Chapter 10 and series
- Slope of line grade.
tan = -1, slope * 13 - 0* line and y intercept form/2 parts intercept form
ch-1 conic
- Axis equation a normal distance from angle which
- A point equation general
- Conic equation
double point double nap
(Axis line) fixed line called vortex.
Chapter 14, Limits and derivatives
- It's the function for which exists values for x to near left of a.
- Right and same thing is right in.
Algebra limits
Algebra derivatives
= h (x) #0 -h(π).
Standard Derivative [ 1 *] Derivative
Chapter 14; The denial of statement, statement, or, to show the statements.
Chapter 15
- Med, modes idea central points- to - Dispersion.
- Max value - min value Range quartile Deviation.
Deviation to mean + standard of equation
Chapter 16
-
If 2 coins at lead/18 - The probability outcome of formula equation. , Is the following are, the sides, given is side from.
-
A is and - A and B. a ∩ to.
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