angles A, B, and Y are in quadrants 1, 2, 3 respectively such that:
tan A= 2
tan B= -4/3
cos Y= -1/3
evaluate the following:
1)cos(2B)
2)tan(2A)
3)cos(Y/2)
4)tan(Y/2)
5)sin(B/2)
6)csc(2B)
7)sec(A/2)