Let be any function between non-empty sets and

MATHEMATICS · Single correct · CBSE · Mathematics · Relations and Functions · Relations and Functions

Problem

Let

f:A\to B

be any function between non-empty sets

A

and

B

I_A

and

I_B

denote the identity functions on

A

and

B

respectively. Which one of the following equalities holds for every such function

f

? (a)

I_A\circ f = f

(b)

f\circ I_A = f

(c)

f\circ I_B = f

(d)

I_B\circ f = I_A