Question

plz solve it.....fastly

Answer 1

Here is your Answer!

$1 - 2 \sin^{2} ( { \sin }^{ - 1}x) = 1 - 2 {x}^{2} \\ \\let \: a = {sin}^{ - 1} x \\ x = sin \: a \\ lhs \\ \\ = 1 - 2 { \sin}^{2}a \\ \\ = 1 - 2 {x}^{2} \\ proved$