Name: ___________________Date:___________________

 Email us to get an instant 20% discount on highly effective K-12 Math & English kwizNET Programs!

### High School Mathematics - 24.3 Identity, Constant and Equal Functions

 Constant Function A function f: A ->B is called a constant function if every element of A is associated with the same element of B, i.e the range of f consists of only one element as shown. Example: Let A = {2,3,5,7,11} and B = {0,7,14, 21}, then f = {(2,0), (3,0), (5,0),(7,0), (11,0)} is a constant function. Identity Function Let A be any set. A function f: A ->A is called an identity function if for every x € A,f(x) = x. i.e if every element is mapped onto itself. It is denoted as IA. Then IA(x) = x for all x € A. Example: Let A = {1,2,3,4}, then f = {(1,1), (2,2), (3,3), (4,4) } is an identity function. Equal Function Two functions f and g are said to be equal written as f = g if they have the same domain and they satisfy the condition f(x) = g(x) for all x. Example: Consider function f defined as shown below in the diagram let a function g be defined by the formula g(x) = x2 where the domain of g is {1,2}. Then f = g since they both have the same domain and since f and g both assign the same image to each element in the domain. Directions: Answer the following.

 Name: ___________________Date:___________________

### High School Mathematics - 24.3 Identity, Constant and Equal Functions

 Q 1: Two functions are equal if they have the same ____.rangedomainfunctions cannot be equal Q 2: Let f: A -> B and g: B -> C be two functions, and f and g both are one-to-one, then gof is ____.constantone-oneonto Q 3: Answer: Q 4: A function f: A -> B is called a ____ function, if all elements in A is mapped to the same element in B.constantconstantidentity Q 5: Answer: Q 6: Answer: Q 7: Answer: Q 8: Answer: Question 9: This question is available to subscribers only! Question 10: This question is available to subscribers only!