Originally Posted by

**B9766** SlipEternal and TopsQuark:

First, thanks again for sticking with me on this. I think I finally get it. A big part of my initial problem was the inability to identify exactly where the disconnects existed in my mind. I'm only part way through this pre-calc class and don't have the benefit of learning all the trig covered in it yet. For example, the next chapter covers sum and difference formulas - so I'm not there yet.

I was going to go into detail about what finally made it all gel for me but it came down to graphing the curves, sine values and actual angles in their quadrants, plus your equations and prompting. Once I was able to visualize the relationships of the angles to the sine function, I could see the $\displaystyle sin(\theta) = sin(\pi/2-\theta)$ equivalence.

Thank you.