Question

if x and y are accute angles such that sinx=8/17xncosy=12/13 find the value of sin(x+y)

Answer 1

sin(x+y)=sinxcosy+cosxsiny to find siny use identity involving cosy and to find cosx use identity involving sinx i.e sin^2 y =1 - cos^2 y and cos^2 x = 1 - sin^2 x or u can use traingle method also to find sin y and cos x