Is There a Straightforward Proof for the Cosine Rule?

AI Thread Summary
The discussion centers on the search for a straightforward proof of the cosine rule in mathematics, particularly in preparation for an upcoming exam. The original poster expresses difficulty in finding a simple proof, noting that existing ones appear too advanced. A user suggests checking Wikipedia, which offers various proofs for the cosine rule. The original poster acknowledges this suggestion and expresses gratitude for the resource. The conversation highlights the challenge students face in understanding mathematical 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
 
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Thats perfect thanks.. Stupid me, I turn to wikipedia for everything else.!
 
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