What is 15pi-2? Thanks in advance for the help!
Each 2 pi is a trip around the circle and doesn't affect the answer.
15 pi/2 = 6 pi + 3pi/2 so tan(15pi/2) = tan(3pi/2) and that is undefined because sin(3pi/2) = -1
and cos(3pi/2) = 0
and (-1/0) is division by 0 and that is undefined.
15*pi-2 = 45.1238898038468986
15pi-2 is already in its most simple form.
You can approximate it but you cannot simplify it.