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# C3 trig identities help watch

1. I've got to work out
Cosecx=3sinx in the interval 0<x<360

And

Cotx=2tanx in the interval -180<x<180

I'm guessing there kinda the same working out, but I don't know how to do it, any helps.
Thanks
2. Firstly, what is equal to?

Then consider the same for in the second question.
3. I get that cosecx = 1/sinx

But what do from 1/sinx=3sinx
4. (Original post by chloeaj95)
I get that cosecx = 1/sinx

But what do from 1/sinx=3sinx
what do you usually do to remove fractions from equations
5. So then you get 1=3sin^2x

But still can't get that into the interval
6. (Original post by chloeaj95)
So then you get 1=3sin^2x

But still can't get that into the interval
Why not?

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Updated: October 14, 2012
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