Question

sin^2(180-α)+sin^2(270-α)

Answer 1

=sin^2a+cos^2a=1 вот ответ

Answer 2

$sin^2 (180^o-a)+sin^2 (270^0-a)=\\sin^2 a+(-cos a)^2=\\sin^2 a+cos^2 a=1$