How do you Identify the point (x,y) on the unit circle that corresponds to t=-3.14/2?
(x,y) coordinates of
The unit circle is used for both degree measure and radian measure. In this case,
Before we get to defining points on the unit circle in terms of radian measure, let's review the (x, y) coordinates of
At 0º, we know that
Now that we've reviewed those, we can start defining points on the unit circle. The difference between radians and degrees is that radians deal with the DISTANCE around the circle, while degrees deal with the MEASURE of the circle as it continues on.
We know that the circumference a circle is:
Since the unit circle has a radius of only one, a full revolution is
Now all we have to do is use that to find
We know that we if we divide
Also, we know that there are
When we solve that we get: