Trig proof with two angles and many functions

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SUMMARY

The discussion focuses on proving the identity cotA cotB = (cscB + cotA) / (tanA secB + tanB). Participants emphasize the importance of converting all functions to sines and cosines to simplify the proof. The hint provided suggests starting from the right side of the equation and combining fractions to facilitate the proof. Ultimately, the approach leads to a successful resolution of the problem.

PREREQUISITES
  • Understanding of trigonometric identities, including cotangent, cosecant, tangent, and secant.
  • Familiarity with the Pythagorean identities, particularly 1 + cot²x = csc²x.
  • Ability to manipulate complex fractions in algebraic expressions.
  • Knowledge of converting trigonometric functions into sine and cosine forms.
NEXT STEPS
  • Practice proving trigonometric identities using sine and cosine conversions.
  • Explore advanced trigonometric identities and their applications in calculus.
  • Learn about the properties of complex fractions and their simplification techniques.
  • Study the derivation and applications of Pythagorean identities in trigonometry.
USEFUL FOR

Students studying trigonometry, educators teaching trigonometric identities, and anyone looking to enhance their problem-solving skills in trigonometric proofs.

stevensen
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Homework Statement


Prove:
cotAcotB=(cscB+cotA)/(tanAsecB+tanB)


Homework Equations


cotx=1/tanx, etc.
I tried using pythagorean identities, like 1+cot2x=csc2x, and others, but I've been unable to solve the problem.


The Attempt at a Solution


Please help me out. The examples in my textbook don't seem very useful here. I've tried everything I could think of.
 
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You need to show some work, but here's a big hint. Start from the right side. Convert everything in terms of sines and cosines. You'll have a complex fraction. Add the two fractions in the numerator, and then add the two fractions in the denominator. Take it from here.
 
Thanks. I finally figured it out.
 

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