`cos 2theta cos 2phi + sin^2(theta-phi)-sin^2(theta+phi)=cos(2theta + 2phi)`

cos2thetacos2phi+sin^2(theta-phi)-sin^2(theta+phi)=

cos2 theta cos2 phi+sin^(2)(theta-phi)-sin^(2)(theta+phi)=cos(2 theta+2 phi)

Prove that sin^2(theta-phi)-sin^2(theta+phi)= -sin2theta sin2phi hence prove that cos2thetacos2phi-sin^2(theta+phi)+sin^2(theta-phi)=cos(2theta+2phi)

Prove that: cos2 theta*cos2 phi+cos^(2)(theta+phi)-cos^(2)(theta-phi)=cos(2 theta+2 phi)

cos2thetacos2phi+sin^(2)(theta-phi)-sin^(2)(theta+phi) is equal to

Prove that cos 2 theta cos 2 phi + sin ^(2) ( theta - phi) -sin ^(2) (theta + phi) = cos ( 2 theta + 2 phi).

cos 2theta cos 2phi + sin^(2) (theta - phi ) - sin^(2) ( theta + phi) is equal to

"cos"2theta."cos"2phi+"sin"^(2)(theta-phi)-"sin"^(2)(theta+phi) is equal to (i) "sin"2(theta+phi) (ii) "cos"2(theta+phi) (iii) "sin"2(theta-phi) (iv) "cos"2(theta-phi)