Question

Упростить Sin2a/cosa+cos2a/sina=?

Answer 1

$frac{sin2a}{cosa}+ frac{cos2a}{sina}=frac{2sina*cosa}{cosa}+ frac{cos^2a-sin^2a}{sina}=2sina+frac{cos^2a-sin^2a}{sina}= \ = frac{2sin^2a+cos^2a-sin^2a}{sina}=frac{sin^2a+cos^2a}{sina}= frac{1}{sina}$