Thread: Domain question.

Hi, I'm having a little trouble understanding how the domain of trig problems work. For example:

If and find the exact value of

Now I know how to solve this and get the answer , but I don't understand how the answer can have a negative value when is positive in the first quadrant. I'm sure it must something to do with the , and that I'm missing something really fundamental here??

Thanks heaps for your help!

Originally Posted by Stroodle

Hi, I'm having a little trouble understanding how the domain of trig problems work. For example:

If and find the exact value of

Now I know how to solve this and get the answer , but I don't understand how the answer can have a negative value when is positive in the first quadrant. I'm sure it must something to do with the , and that I'm missing something really fundamental here??

Thanks heaps for your help!

2x is in the second quadrant ....