Question

Упростите выражение: 5 sin2 x – 4 + 5 cos2 x.

Answer 1

5 sin2 x – 4 + 5 cos2x=-4sin^2x-4cos^2x+5cos^2x-5sin^2x+5sin2x=cos^2x+sin^2x-10sin^2x+10sinxcosx=1-10sinx(sinx-cosx)