Question

9sinx-9cosx+2sin2x-2=0

Answer 1

$9sinx-9cos x+2sin(2x)-2=0$
$9sin x+2sin x cos x-9cos x-2=0$
$sinx(9+2cos x)-1*(9cos x+2)=0$
$(sin x-1)(9cos x+2)=0$
$9cos x+2=0;cos x=-frac{2}{9}$
$x=^+_-(pi-arccos frac{2}{9})+2*pi*k$
$sin x-1=0;sin x=1$
$x=frac{pi}{2}+2*pi*n$
k, n є Z

Answer 2

не могли бы помочь?