Question

Given A={2,3,4}, B={2,5,6,7}. Construct an example of the following.

an injective mapping from A to B

Answer 1

$A=\{2,3,4\},B=\{2,5,6,7\}$
A mapping from set A to set B is injective if distinct elements of A have distinct images of B.
So, $f=\left\{\right(2,2),(3,5),(4,7\left)\right\}$or $f=(2,6),(3,5),(4,7)$ or $f=\left\{\right(2,7),(3,5),(4,2\left)\right\}$.....