Question

given A = 60° and B = 30°, prove that:
sin (A + B) = sin A cos B + cos A sin B​

Answer 1

Answer:

sin(60+30) = sin 60.cos30 + cos60.sin30

sin90 =√3/2 × √3/2 + 1/2 × 1/2

(because sin60 = √3/2. cos30 = √3/2. cos60 =1/2. sin30 = 1/2 )

1 = 3/4 + 1/4 (sin 90 = 1)

1 = 4/4

1=1

hence proved