`cos (A+B).cos(A-B)=cos^(2)A-sin^(2)B`

Prove that cos (A + B) cos (A - B) = cos^(2) B - sin^(2) A

Prove that sin(A+B)sin(A-B)=sin^(2)A-sin^(2)B=cos^(2)B-cos^(2)A

Prove the following identities: tan^(2)A-tan^(2)B=(cos^(2)B-cos^(2)A)/(cos^(2)B cos^(2)A)=(sin^(2)A-sin^(2)B)/(cos^(2)A cos^(2)B)(sin A-sin B)/(cos A+cos B)+(cos A-cos B)/(sin A+sin B)=0

If (cos A)/(cos B)=p,(sin A)/(sin B)=q ,then (p^(2)(q^(2)-1))/(p^(2)-q^(2)) is equal to (A)-cos^(2)A(B)cos^(2)B(C)cos^(2)A(D)sin^(2)B

Prove that sin (A+B) sin (A-B)=cos^(2) B-cos^(2) A

Evaluate sum(sin (A+B)sin(A-B))/(cos^(2)A cos^(2)B) : if non of cos A , cos B, cos C is zero.

sin^(2)A cos^(2)B-cos^(2)A sin^(2)B=sin^(2)A-sin^(2)B

cos(A+B)*cos(A-B)= (a) sin^2A-cos^2B (b) cos^2A-sin^2B (c) sin^2A-sin^2B (d) cos^2A-cos^2B

Prove that sin ^(2) A cos ^(2) B+cos ^(2) A sin ^(2) B+cos ^(2) A cos ^(2) B+sin ^(2) A sin ^(2) B=1

Prove that tan^2A - tan^2B = (sin(A+B).sin(A-B))/(cos^2A.cos^2B