In this case, it is perhaps simplest to use the addition formula for sine,
Since sin(3)=32 , cos(3)=12, sinv=a, and cosv=1−a2 this can be written as
3+v
=sin3
cosv+cos3sinv. 
3)=
32 3)=12
1−a2 3+v=231−a2+21a. 