Need help with Trig please i dont understand
cos θ - cos θ sin2θ

Question

Need help with Trig please i dont understand 
cos θ - cos θ sin2θ

anonymous · Answer

Need help with trig pleasse :)

anonymous · Answer

Is this supposed to be an equation? Or what do you need to do with it?
The way this is written at the moment it's just a trigonometric expression.

anonymous · Answer

I need to simplfy  the equation

anonymous · Answer

Hmm I see, it's a bit of a rough statement to me, because simplifying a trigonometric expression usually involves restrictions such as "express in terms of cosx only"

anonymous · Answer

well it says to use the identities but i dont get which one to use

anonymous · Answer

You may want to use $$\Large \sin(2x)=2\sin x \cos x $$

anonymous · Answer

so then i would sub in sin2x with 2sinx cosx?

anonymous · Answer

yes that's what I would do. But I doubt that this will simplify the equation a lot. It's one one possible way to express the trigonometric identity without a double angle.