Prove that: `cos2alpha\ cos2beta+sin^2(alpha-beta)-sin^2(alpha+beta)=cos2(alpha+beta)` .

Prove that : cos^2alpha+cos^2(alpha+beta)-2cosalphacosbetacos(alpha+beta)=sin^2beta

Prove that : (cos alpha + cos beta)^2 + (sin alpha + sin beta)^2 = 4 cos^2 ((alpha-beta)/(2))

Prove that 2 sin^2 beta + 4 cos(alpha + beta) sin alpha sin beta + cos 2(alpha + beta) = cos 2alpha

Prove that: tan(alpha+beta)tan(alpha-beta)=(sin^2 alpha-sin^2 beta)/(cos^2 alpha-sin^2 beta)

Simplify 2sin^2beta+4cos(alpha+beta)sinalphasinbeta+cos2(alpha+beta)

Show that: sin^2 alpha + sin^2 beta + 2sinalpha sinbeta cos(alpha+beta)=sin^2 (alpha+beta)

Show that cos ^2 alpha + cos^2 (alpha +Beta) - 2 cos alpha cos betacos (alpha+ beta) =sin^2 beta

Q. If tan alpha and tan beta are the roots of equation x^2-12x-3=0 , then the value of sin^2(alpha+beta)+2sin(alpha+beta)cos(alpha+beta)+5cos^2(alpha+beta) is

The expression cos^2(alpha+beta)+cos^2(alpha-beta)-cos2alphacos2beta is

If cosalpha+cosbeta=0=sinalpha+sinbeta, then cos2alpha+cos2beta is equal to (a) -2"sin"(alpha+beta) (b) -2cos(alpha+beta) (c) 2"sin"(alpha+beta) (d) 2"cos"(alpha+beta)