Here is an article that shows that taylor series for sinus becomes very accurate:(adsbygoogle = window.adsbygoogle || []).push({});

http://dotancohen.com/eng/taylor-sine.php

I wondered if I could prove the sinus values. Explanation for taylor formula have I found here before but the proof for derivative of sinus and cosine relies on values for sinx and cosx which is circular. I might as well upload my attempt to prove cosine to show what I mean. (The same problem goes for sinus):

Step1

http://www.viewdocsonline.com/document/4bp3pb

Step2

http://www.viewdocsonline.com/document/8e1qd2

Step3

http://www.viewdocsonline.com/document/tx1cp3

Summary

http://www.viewdocsonline.com/document/5f54l8

The biggest problem of circularity in the proof that I found was that it uses values for sinA and sinB and cosA and cosB to pytagoras theorem in part one for rewriting identity. Does anyone know a way around this to be able to prove values for sinx?

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# Explanation sinus

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