Consider function f : A $\to$ B and g : B $\to$ C (A, B, C $\subseteq$ R) such that (gof)$-$1 exists, then :
Solution
$\therefore$ (gof)<sup>$-$1</sup> exist $\Rightarrow$ gof is bijective<br><br>$\Rightarrow$ 'f' must be one-one and 'g' must be ONTO.
About this question
Subject: Mathematics · Chapter: Sets, Relations and Functions · Topic: Sets and Operations
This question is part of PrepWiser's free JEE Main question bank. 195 more solved questions on Sets, Relations and Functions are available — start with the harder ones if your accuracy is >70%.