Question

Упростите выражение cos^2a-sin^2a/sinacosa

Answer 1

$frac{ cos^{2} alpha - sin^{2} alpha }{sin alpha *cos alpha } = frac{cos2 alpha }{ frac{1}{2}*(2sin*cos alpha ) } = frac{2*cos2 alpha }{sin2 alpha } =2tg alpha$