1. If [itex]x = \cos \theta[/itex] and [itex]y = \cos \theta + \sin \theta[/itex], [itex]\frac{dy}{dx}[/itex] is? (Answer: [itex]1 - \cot \theta[/itex])(adsbygoogle = window.adsbygoogle || []).push({});

I'm just not seeing this question... any help appreciated.

2. [itex]y = \ln(\sec 2x + \tan 2x)[/itex] (Answer = [itex]2\sec 2x[/itex])

I get to [tex]\frac{1}{(2\sec x\tan x) + (2\sec^2 x)}[/tex] but it doesn't seem that I'm on the right track compared to the answers I have.

**Physics Forums | Science Articles, Homework Help, Discussion**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# More differentiation problems

**Physics Forums | Science Articles, Homework Help, Discussion**