Trigonometric Question (easy 10 points if you get it right)?

Question

How exactly do you know what the side measurements are given this problem
1) Find the Cos, Sin, and Tan of: (Pie)/2 (same as 90 degrees)
Does graphing help or what do I need to do to find the side lengths (hyp,opp, and adj) to solve for cos, sin, and tan, thanks
2) Same Question for (Pie)/6

Answer 1

use circle 1 unit
that sin =y cos =x and tan =y/x
draw circle 1 unit (like 10 cm)
1) cos =0 sin =1 tan = inf
2) cos =sqrt(3)/2 sin =1/2 tan = 1/ sqrt(3)

Answer 2

for pi/2
sin = 1 cos =0 and tan does not exist
for pi/6
sin =1/2 cos = sqrt3/2 and tan = sqrt3/3