Is There a Straightforward Proof for the Cosine Rule?

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SUMMARY

The discussion centers on the search for a straightforward proof of the cosine rule in mathematics. The user "atwarwithmaths" expresses difficulty in finding a simple proof, noting that existing proofs appear advanced. A suggestion is made to refer to Wikipedia, which provides various proofs of the cosine rule. This highlights the utility of Wikipedia as a resource for mathematical concepts.

PREREQUISITES
  • Understanding of basic trigonometric concepts
  • Familiarity with the sine rule
  • Knowledge of triangle properties
  • Basic mathematical proof techniques
NEXT STEPS
  • Research various proofs of the cosine rule on Wikipedia
  • Study the sine rule and its proofs for comparative understanding
  • Explore geometric interpretations of the cosine rule
  • Practice problems involving the application of the cosine rule
USEFUL FOR

Students preparing for mathematics exams, educators teaching trigonometry, and anyone interested in understanding geometric proofs.

atwarwithmaths
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Hi Guys/Girls,

I have a maths exam tomorrow and there is a chance I could be asked to prove the cosine rule or sine rule.

Well I have a simple proof of the sine rule but cannot find a simple one for the cosine. They all seem very advanced.

Would anybody have a straightforward proof for the cosine rule?

Thanks,
atwarwithmaths
 
Mathematics news on Phys.org
Thats perfect thanks.. Stupid me, I turn to wikipedia for everything else.!
 

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