help (trigonometry ) | Mathematics | Page 1

fair wasp Jun 10, 2023, 4:27 PM

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steady linden Jun 10, 2023, 5:02 PM

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fair wasp

Hint: Apply sum of cubes on the LHS

fair wasp Jun 10, 2023, 5:03 PM

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What about the rhs ?

steady linden Jun 10, 2023, 5:04 PM

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The idea is that you're supposed to manipulate one of the sides to end up with the result on the other side

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In this case, it's more intuitive (at least for me) to manipulate the LHS

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Since we're normally better at making messy things simpler than making simple things messy

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But once you apply sum of cubes, you'll see how stuff reduces

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Especially once you use the ||Pythagorean identity||

fair wasp Jun 10, 2023, 5:05 PM

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Lhs will be equaled to this

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So don’t we need to do the mhs and rhs to prove to be this identity

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?

steady linden Jun 10, 2023, 5:07 PM

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Can you send all your working so far?

fair wasp Jun 10, 2023, 5:07 PM

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It’s pretty rough I will do it again

steady linden Jun 10, 2023, 5:07 PM

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👍

fair wasp Jun 10, 2023, 5:07 PM

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Gimme a min

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Stuck form here

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steady linden Jun 10, 2023, 5:16 PM

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Note that $\sin \theta \cos \theta=\frac{1}{2}\sin 2\theta \implies \sin^2 \theta \cos^2 \theta =\frac{1}{4} \sin^2 2\theta$

deep lintelBOT Jun 10, 2023, 5:17 PM

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Civil Service Pigeon

fair wasp Jun 10, 2023, 5:20 PM

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Ah i see

steady linden Jun 10, 2023, 5:22 PM

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Can you take it from here?

#help (trigonometry )