Simplify:
`sin (B + C) sin (B - C) + sin (C + A) sin (C - A) + sin(A + B) sin (A - B)`

sin (B + CA) + sin (C + AC) + sin (A + BC) = 4sin A sin B sin C

Simplify: cosA sin(B - C) + cos B sin (C - A) + cosC sin(A -B)

If p = sin (A-B) sin (C-D) q = sin (B-C) sin (A-D) , r = sin (C-A) sin (B- D) then

a sin A-b sin B=c sin(A-B)

a sin A-b sin B=c sin(A-B)

a sin A-b sin B=c sin(A-B)

Prove that (sin (A - B))/( sin A sin B ) + ( sin (B -C))/( sin B sin C ) + (sin (C - A))/( sin C sin A) =0

Simplify: (sin(A - B))/(sin A sin B) + (sin(B - C))/(sin B sin C) + (sin (C - A))/(sin C sin A)

(sin(A - B))/(sin A sin B) + (sin(B - C))/(sin B sin C) + (sin (C - A))/(sin C sin A)=0