SOLUTION: Suppose Θ is in standard position whose terminal side lies in Quadrant II. Find the exact values of the remaining five trigonometric functions for Θ for
cos Θ = -
If = and is in QII then
= = = = = .
The sign "+" was chosen at the square root since sine is positive in QII.
Now, when you know that = and = , you can easily calculate all other trigonometric functions of .