Posted by Paige on .
find (s+t) given that cos s=1/3 with s in quad I and sin T=1/2 with t in quad IV

Trig 
Reiny,
I have a feeling that you want exact values for
sin(x+t) or cos(s+t)
the way it stands, just use your calculator to find each of the angles, then add them up. 
Trig 
Paige,
No it is to find the exact value of the expression using the provided information. Find Tan (S+T) given that cos s=1/3 with s in quad I and sin T= 1/2 with T in quad IV