Question

Упростите выражение 7sin^x -5 +7 cos^2x+2

Answer 1

$7sin^{2}x-5+7cos^{2}x+2=0 \ \ (cos^{2}x=1-sin^{2}x) \ \ 7sin^{2}x-5+1-sin^{2}x+2=0 \ 6sin^{2}x-2=0 \ sin^{2}x= frac{1}{3} \ sinx= sqrt{ frac{1}{3}} \ x=arcsinsqrt{ frac{1}{3}}+ pi n$