Question

if A,B, C,D be the angles of a quadrilateral then prove that sin A + Sin ( B, C,D)= 0​

Answer 1

Question :

If A,B,C and D are the angles of a quadrilateral, then sin (A+B)+sin(C+D) is equal to ?

Answer :

Since A,B,C,D are angles of quadrilateral

A + B + C + D = 360 = 2 $\pi$

Therefore, sin(A+B)+sin(C+D)

=sin(A+B)+sin(2π−(A+B))

=sin(A+B)−sin(A+B)

=0

Hence answer is option C.