Prove the following:`sin[(n+1)A].sin[(n+2)A]+cos[(n+1)A].cos[(n+2)A]=cosA`

Prove the following: sin(A+B).sin(A-B)=cos^2B-cos^2A

Prove the following: sin^6A+cos^6A=1-3sin^2A+3sin^4A

Select the correct options from the given alternatives.The value of sin(n+1)Asin(n+2)A+cos(n+1)Acos(n+2)A is equal to….

Prove the following: sin^-1(frac{-1}{2})+cos^-1(frac{-sqrt3}{2}) = cos^-1(frac{-1}{2})

sin A=1/2, cosA=?

Prove the following: cottheta(1-cos2theta)=sin2theta

Prove the following: sin^4theta+2sin^2thetacos^2theta=1-Cos^4theta

Prove the following: cos^4theta-sin^4theta+1=2cos^2theta