(sin^2)*x+2sinx-(3cos^2)*x+1=0

Sin²x+2sinx-3+3sin²x+1=0 sinx=a 4a²+2a=2=0 2a²+a-1=0 d=1+8=9 a1=(-1-3)=-/⇒sinx=-⇒x=-π/+πn,n∈z a=(-+)=//⇒sinx=/⇒x=(-)^n*π/+πk,k∈z