## Equivalent expressions Trig: sin theta + cos theta ( sin theta/cos theta)

Trigonometric ratios and functions, the unit circle, inverse trig functions, identities, trig graphs, etc.
lmuegge
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### Equivalent expressions Trig: sin theta + cos theta ( sin theta/cos theta)

What is the equivalent of the following expression sin theta + cos theta cot theta.

I have been trying to work this.
I started by finding equivalent for cot theta.
sin theta + cos theta ( sin theta/cos theta)
This gave me sin theta = cos theta sine beta + 1

little_dragon
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### Re: Equivalent expressions Trig: sin theta + cos theta ( sin theta/cos theta)

What is the equivalent of the following expression sin theta + cos theta cot theta?
I don't know if there is a "the" equivalent
maybe there's LOTS of equivalents!
(these Qs aren't really fair, I think)
I started by finding equivalent for cot theta.
sin theta + cos theta ( sin theta/cos theta)
This gave me sin theta = cos theta sine beta + 1
where did "beta" come from?
how does it relate to theta?
how did you get an equation when you started w/ an expression?
thnx

lempirintanen
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### Re: Equivalent expressions Trig: sin theta + cos theta ( sin theta/cos theta)

The little mistake you made is that cot is cos/sin and not sin/cos. The final answer is csc.
Last edited by lempirintanen on Wed Jan 04, 2017 2:10 am, edited 1 time in total.

maggiemagnet
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### Re: Equivalent expressions Trig: sin theta + cos theta ( sin theta/cos theta)

The little mistake you made is that cot is cos/sin and not sin/cos. The final answer is csc.
Just FYI: Sine, cosine, tangent, etc, are functions, so they need arguments. Just as you wouldn't say "ln", because natural log needs to be the log of something, so also you can't say "sin" and "cos" without their arguments. Also, teachers usually count off for this sort of thing as being sloppy and incomplete. So don't drop the arguments!