Solve Hard C3 Question: Get Rid of cosec²x - cot²x

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The discussion centers on solving the trigonometric identity involving cosecant and cotangent functions, specifically the expression cosec²θ - cot²θ. The key conclusion is that cosec²θ - cot²θ simplifies to 1, while cosec²θ + cot²θ equals -1. The user successfully applies the difference of squares method and confirms that the original equation simplifies correctly to -1 = -1, validating their approach. The discussion emphasizes the importance of utilizing previously established results in problem-solving.

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im stuck on the top question on part B

i can do the difference of 2 squares on the LHS but how do i get rid of the cosec²x - cot²x ??

Thanks
 
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mis-post, oops!

Edit: Well, as I'm here...

cosec^2\theta - cot^2\theta = 1
cosec^2\theta + cot^2\theta = -1

Well, that's the RHS...

-cot^4\theta = -cot^2\theta \times cot^2\theta\newline
= (1 - cosec^2\theta)(cosec^2\theta - 1)\newline
= -1 + cosec^2\theta - cosec^4\theta - cosec^2\theta\newlineBack to the original question!

cosec^4\theta - cosec^4\theta - 1 = - 1\newline
-1 = -1I think that's correct :S

(Hmm, latex is messed up, how do I make a newline?)
 
Last edited:
Use the result in part a) like it told you to.
 
3lliot, please do not give out answers. We offer free help here at PF, not free answers.
 

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