`-cos(A+B)cos(B-A) =`

Prove (i)cos(A+B)+cos(A-B)=2cos A cos B(ii)cos(A-B)-cos(A+B)=2sin A sin B

For any angles A and B, cos(A+B).cos(A-B)=…..

cos(-A+B+C)+cos(A-B+C)+cos(A+B-C)+cos(A+B+C)=4cos A cos B cos C

Prove that: (sin(A+B)+sin(A-B))/(cos(A+B)+cos(A-B))=tan A

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

(cos(-A+B+C)+cos(A-B+C)+cos(A+B-C)+cos(A+B+C))/(sin(-A+B+C)-sin(A-B+C)+sin(A+B-C)+sin(A+B+C))=cot B

Prove that: (cos(A+B+C)+cos(-A+B+C)+cos(A-B+C)+cos(A+B-C))/(sin(A+B+C)+sin(-A+B+C)+sin(A-B+C)-sin(A+B-C))=

Prove that (1-cos A+cos B-cos(A+B))/(1+cos A-cos B-cos(A+B))=tan((A)/(2))cot((B)/(2))

(1-cos A+cos B-cos(A+B))/(1+cos A-cos B-cos(A+B))=(tan A)/(2)(cot B)/(2)