Question

Let $f:\left[-\frac{\pi }{2},\frac{\pi }{2}\right]\to$ A be defined by f(x) = sin x. If f is a bijection, write set A.

Answer 1

$\because$f is a bijection,
co-domain of f = range of f
As $-1\le \sin x\le 1$,
$-1\le y\le 1$
So, A = [-1, 1]