# Who wants to help me with trig identities?!

**URL:** <https://forum.kirupa.com/t/who-wants-to-help-me-with-trig-identities/284400>\
**Category:** random\
**Created:** [March 18, 2009, 8:47pm UTC](https://forum.kirupa.com/t/who-wants-to-help-me-with-trig-identities/284400 "2009-03-18T20:47:19Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![nobody](https://avatars.discourse-cdn.com/v4/letter/n/94ad74/32.png) [@nobody](https://forum.kirupa.com/u/nobody)\
**Post date:** [March 18, 2009, 8:47pm UTC](https://forum.kirupa.com/t/who-wants-to-help-me-with-trig-identities/284400/1 "2009-03-18T20:47:19Z")

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Good times, I know. I have my precalc final today and I am surely going to bomb it unless I can figure stupid stuff like this out.

Below is the answer to one of my practice problems (in comic sans!) - I don’t get the second step (the first equation with no left side)

![](http://dl.getdropbox.com/u/27107/stupid/isuckatmath.png)

How does 1+cos^2(x) turn into sin^2x + cos^2x

Bleeehhhh