Question

sin (B+C) + sin (C+A) + sin (A+B)÷
sin (180+A) + sin (3×180+B) + 6 sin (5×180 + c) = -1​

Answer 1

Step-by-step explanation:

LHS=sin(b+c-a) +sin (a+c-b)+sin (a+b-c) =( sin(b+c)cosa -cos (b+c)sina ) +( sin(a+c)cosb