Prove that `sum_(r=1)^n(1/(costheta+"cos"(2r+1)theta))=(sinntheta)/(2sintheta* costheta*cos (n+1)theta),(w h e r e n in N)dot`

(sintheta+sin2theta)/(1+costheta+cos2theta) =

(sintheta+sin2theta)/(1+costheta+cos2theta)=?

Prove that : (1-costheta)/(sintheta)+(sintheta)/(1-costheta)=2"cosec "theta

(sintheta)/(1+costheta) + (1+costheta)/(sintheta) = 2 cosec theta

If : (sintheta+costheta)(1-sintheta*costheta)=sin^(n)theta+cos^(n)theta,"then" : n =

Prove that : (cos^(2)theta)/(1-tantheta)+(sin^(3)theta)/(sintheta-costheta)=1+sinthetacostheta

Prove that : (sintheta)/(1+costheta)+(1+costheta)/(sintheta)=2"cosec"theta

Prove that: (sin2theta)/(costheta cos3theta)+(sin4theta)/(cos3theta.cos5theta)+(sin6theta)/(cos5theta.cos7theta)+… to terms = 1/(2sintheta) [sec(2n+1)theta-sectheta]

((1+sintheta+i costheta)/(1+sintheta-i costheta))^n is equal to