Question

Прошу помогите!Срочно...
cos^2x=sinx-1​

Answer 1

$cos^2(x)=sin(x)-1<=>1-sin^2(x)=sin(x)-1<=>\\<=>sin^2(x)+sin(x)-2=0\\a+b+c=0\\sin(x)=1=>x=\frac{\pi}{2}+2\pi k$

sin(x)=-2⇒x∈∅

$x=\frac{\pi}{2}+2\pi k$

k∈Z