#### Please Solve RD Sharma Class 12 Chapter Function Exercise 2.4 Question 24 Subquestion (i) Maths Textbook Solution.

$fog$ is an injection.

Given:

$f:A\rightarrow A,g:A\rightarrow A$
Hint:
Injection means every domain has a distinct range.
Solution:
Let $x,y$ be two elements of the domain $\left ( A \right )$ such that

$\left ( fog \right )\left ( x \right )=\left ( fog \right )\left ( y \right )$

$f\left ( g\left ( x \right ) \right )=f\left ( g\left ( y \right ) \right )$

$g\left ( x \right )= g\left ( y \right )$   [As,$f$ is one-one]

$x=y$  [As,$g$ is one-one]

So, $fog$ is an injection.