Question

On a unit circle, the terminal point of is (1/2, (sqrt(3))/2) What is cos ?

Answer 1

Answer: 1/2

Reason:

The x coordinate of the point on the unit circle corresponds to
`\cos(\theta)`

The formulas to write down and memorize are

`\text{x} = \cos(\theta)\\\\\text{y} = \sin(\theta)`

where the angle theta (symbol
`\theta`) is measured starting at the positive x axis, and you move counterclockwise.

Side note: Trigonometry is useful for things like navigation.