- #1
Andrusko
- 44
- 0
I'm following through a solution to a problem I couldn't do and there's a bit of trig manipulation I can't get my head around:
2cos^{2}x - sin^{2}x = 2 - 3sin^{2}x
I tried using this identity to get it to work:
cos^{2}x - sin^{2}x = 1 - 2sin^{2}x
but alas, I could not. And after that I have no more ideas.
If someone could point out how this transforms that'd be great. Evil, evil trig...
2cos^{2}x - sin^{2}x = 2 - 3sin^{2}x
I tried using this identity to get it to work:
cos^{2}x - sin^{2}x = 1 - 2sin^{2}x
but alas, I could not. And after that I have no more ideas.
If someone could point out how this transforms that'd be great. Evil, evil trig...