If sin alpha 35 and sin beta 1213 alpha and beta are in Qu
     If sin alpha = 3/5 and sin beta = 12/13 alpha and beta are in Quadrant 1. Draw a diagram to assist you  a. Find cos (alpha) exactly  b. Find tan (beta) exactly  c. Find sin (alpha + beta) exactly 
  
  Solution
sin alpha=3/5
cos alpha=sqrt(25-9)/5 = 4/5
sin beta=12/13
cos beta=sqrt(169-144)/13 =5/13
tan beta=sin beta/cos beta =12/5
sin(alpha+beta)=sin alpha cos beta +cos alpha sin beta
=(3/5)(5/13)+(4/5)(12/13) =63/75=21/25

