(cscX/cotX)-(cotX/cscX) in terms of sinX, cosX, verify ident

WolfSpice

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Feb 25, 2009
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1) Write (cscX/cotX)-(cotX/cscX) in terms of sinX and cosX and simplify. I've tried it a few ways on this one but it never seems to get in any simpler form, I feel like I'm missing something.
I went through these steps:
(cscX/cotX)-(cotX/cscX)=(1/sinX)/(cosX/sinX)-(cosX/sinX)/(1/sinX)=(1/sinX)^2/(cosX/sinX)*(1/sinX)=((1/sinX)^2-(cosX/sinX)^2)/((cosX/sinX)*(1/sinX)) which simplfies to (1/sinX)-(cosX/sinX) which simplifies to 1-cosX right? Is that as far as I can go or is there an identity I'm missing for it? (actually, now that I think about it, is it possible to eliminate the denominator (cosX/sinX)*(1/sinX) because it is being multiplied?

2) Verify the identitiy (sinX/1-cosX)=(1+cosX/sinX). I'm just not sure where to go here either.
 
On 1 I get sin[sup:mmtt3t7i]2[/sup:mmtt3t7i]x/cos x which can simplify to tanx sinx.

On 2, multiply numerator and denominator on the left side by 1+cos x and go from there.
 
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