What are the steps to simplify a trig identity with multiple angles?

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SUMMARY

The discussion focuses on simplifying the trigonometric identity (sin 3α/sin α) - (cos 3α/cos α) = 2. Participants emphasize the use of angle-sum formulas for sine and cosine to rewrite sin 3α and cos 3α. Specifically, sin 3α can be expressed as 3sinα - 4sin³α, while cos 3α can be rewritten as 4cos³α - 3cosα. The goal is to combine these terms over a common denominator of sinα cosα to facilitate simplification.

PREREQUISITES
  • Understanding of trigonometric identities, specifically angle-sum formulas.
  • Familiarity with the sine and cosine functions and their properties.
  • Basic algebraic manipulation skills for combining fractions.
  • Knowledge of polynomial expressions in trigonometric contexts.
NEXT STEPS
  • Study the derivation and application of angle-sum formulas for sine and cosine.
  • Learn how to simplify complex trigonometric expressions using common denominators.
  • Explore the identities for sin 3α and cos 3α in detail.
  • Practice solving similar trigonometric identities to reinforce understanding.
USEFUL FOR

Students studying trigonometry, educators teaching trigonometric identities, and anyone looking to enhance their skills in simplifying complex trigonometric expressions.

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Homework Statement



(sin 3α/sin α) - (cos 3α/cosα) =2

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The Attempt at a Solution



I know for sin 2 α I would put 2 sinαcosα, so for 3α, do I just put 3sinαcosα?
for cos 3α, I'm sort of clueless because there's 3 we can use for cosine,
Then after that step, I know to get both of them on the LHS to have a common denominator, which sinα cosα, please help. Thank yyou in advance!
 
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Start with the angle-sum formulas.
 

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