# Thread: Help with problem involving terminal angles?

1. ## Help with problem involving terminal angles?

Hello everyone. Our professor explained to us how to get the terminal angles of a unit circle. In this particular question though (see attached picture), I don't know how to solve the terminal angle without any angle measure given... Please guide me in the right direction.

Thank you very much!

2. ## Re: Help with problem involving terminal angles?

Originally Posted by kaonashi
Hello everyone. Our professor explained to us how to get the terminal angles of a unit circle. In this particular question though (see attached picture), I don't know how to solve the terminal angle without any angle measure given... Please guide me in the right direction.
It appears that your professor and/or your text material has particular meaning for "terminal point".
Please tell us what it means.

Any of the given points can be on the terminal ray of an angle.
a & c are in the second quadrant, the other two are in the first. Does the make a difference?

3. ## Re: Help with problem involving terminal angles?

It looks the terminal point has to lie on the unit circle, so just one of them fits.

4. ## Re: Help with problem involving terminal angles?

The unit circle. If (x, y) is on the unit circle, what must be true of $\displaystyle x^2+ y^2$?