Question

Решите:
1-3/4sin^2 (2a)+3/4cos^2 (2a)

Answer 1

$1- frac{3}{4} sin^2 (2 alpha )+ frac{3}{4} cos^2 (2 alpha )=1- frac{3}{4}(cos ^{2}2 alpha -sin ^{2}2 alpha )=1- frac{3}{4}cos4 alpha$