Finding Exact Value of Sine

All right, I am going to find Sin(135degrees) 

All you have to do for this problem is:

1. Do 135-180 (Because you must find a degree between 0-90 degrees) and get Sin(-45degrees), though you should ignore the negative and get Sin(45degrees) because Sin(135) has to be equal to the angle you find. If you enter sin(135) and Sin(45) into your calculator, you will find that they are the same value.

2. You would then refer to a Trig Chart and find Sin(45degrees) and look for the numerical value.

3. Once you find it you'll see the square root of 2 over 2; that will be your final answer.