Question

If A, B and C are the angles of a triangle, prove that sinBcosC+cosBsinC=sinA

Answer 1

Plug in an angle for each

Answer 2

A+B+C=180
A+B=180-C
sin(A+B)=sin(180-C)
sinBcosC+cosBsinC=sinA

Answer 3

got it?

Answer 4

@sauravshakya could you explain the step between
sin(A+B)=sin(180-C)
sinBcosC+cosBsinC=sinA

So sorry and thannks

Answer 5

Looks like I did a simple mistake,
A+B+C=180
B+C=180-A
sin(B+C)=sin(180-A)
sinBcosC+cosBsinC=sinA

Answer 6

Thanks alot!

Answer 7

welcome