+9665 I don't know what the exact problem is but I can give you a tips:
Use Pythagoras theorem and special angles table!!
Pythagoras theorem: The square of the longest side in a right angled triangle is equal to the sum of squares of the other 2 sides.
OR
\(a^2 + b^2 = c^2\)
Special angles table:
| f(x)\x | 30 degrees/ 1/6 pi radians | 45 degrees/ 1/4 pi radians | 60 degrees/ 1/3 pi radians |
|---|---|---|---|
| sin x | \(\dfrac{1}{2}\) | \(\dfrac{1}{\sqrt2}\) | \(\dfrac{\sqrt3}{2}\) |
| cos x | \(\dfrac{\sqrt3}{2}\) | \(\dfrac{1}{\sqrt2}\) | \(\dfrac{1}{2}\) |
| tan x | \(\dfrac{1}{\sqrt3}\) | \(1\) | \(\sqrt 3\) |
