Express the following as a fraction

Question

(sin 50^o)(cos 10^o) + (cos 50^o)(sin 10^o)

Answer 1

The double angle identity is: sin(x+y) = sinx cosy + cosx siny

 

Let x = 50^o and y = 10^o:

 

sin(50^o)cos(10^o)+cos(50^o)sin(10^o) = sin(50^o+10^o) = sin(60^o) = (√3)/2