Question Number 148706 by mathdanisur last updated on 30/Jul/21

Answered by mindispower last updated on 30/Jul/21

sin^2 (x)=((1−cos(2x))/2) (E)⇔2−(1/2)(cos(6x)+cos(8x)+cos(12x)+cos(14x))=2 ⇔cos(6x)+cos(14x)+cos(8x)+cos(12x)=0 ⇔2cos(10x)cos(4x)+2cos(10x)cos(2x)=0 ⇔cos(10x)(cos(4x)+cos(2x))=0 ⇔cos(10x)cos(3x)cos(x)=0 x=(π/2)+kπ x=(π/6)+((kπ)/3),x=(π/(20))+((kπ)/(10)),k∈Z

Commented bymathdanisur last updated on 30/Jul/21

Thank you Ser

Commented bymindispower last updated on 30/Jul/21

withe pleasur