[" 16) "cos(A+B)^(5)*cos(A-B)=],[=cos^(2)A-sin^(2)B]

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

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

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

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

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

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

If A+B+C = pi , show that |["sin"^(2)A, "sin A cos A", "cos"^(2)A],["sin"^(2) B, "sin B cos B", "cos"^(2)B],["sin"^(2)C, "sin C cos C", "cos"^(2)C]| =-"sin (A-B)"sin"(B-C)"sin"(C-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