Find the sum: `costheta+ (a cos2theta)/(1!)+(a^2cos3theta)/(2!)+(a^3cos4theta)/(3!)+…to oo`

Find the sum of the series costheta- (cos2theta)/(2!)+(cos3theta)/(3!)-… to oo

int(costheta-cos2theta)/(1-cos theta)d theta=

cos theta cos2 theta cos3 theta=(1)/(4)

costheta-cos2theta=sin3theta

If tan theta=sqrt((3)/(2)) and the sum of the infinite series 1+2(1-cos theta)+3(1-cos theta)^(2)+4(1-cos theta)^(3)+......+oo is (lambda)/(2) then the value of lambda is (1)2(2)5(3)1(4)4

costheta.cos2theta.cos3theta=1/4

Find the sum of n terms the series: 1/(costheta+cos3theta)+1/(costheta+cos5theta)+1/(costheta+cos7theta)+…

If tan theta=sqrt((3)/(2)), then the sum of the infinite series 1+2(1-cos theta)+3(1-cos theta)^(2)+4(1-cos theta)^(3)+......

If (cos^(2)theta)/(2)=(sin^(2)theta)/(3) find (cos^(4)theta)/(2)+(sin^(4)theta)/(3)