Question

If $f:A\to B,g:B\to C$ are functions such that gof $:A\to C$ is onto, then a necessary condition is

• A. f is onto
• B. g is onto
• C. both f, g are onto
• D. neither f nor g is onto

Answer 1

Answer: (B)

If functions $f:A\to B$ and $g:B\to C$, such that gof $:A\to C$ is onto, then it is necessary that ' $g$ ' is onto.