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Difference between revisions of "Double angle identities"
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==If This Doesn't Makes Any Sense:==
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== Proof ==
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Please Try to Proof it on your own, or try using a Youtube Video, It really helps.
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Please try to prove it on your own.
  
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==See Also==
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== See Also ==
 
* [[Trigonometric identities]]
 
* [[Trigonometric identities]]

Latest revision as of 15:12, 14 February 2025

The trigonometric double-angle identities are easily derived from the angle addition formulas by just letting $x = y$. Doing so yields:

  • $\sin (2x) = 2\sin (x) \cos (x)$
  • $\cos (2x) = \cos^2 (x) - \sin^2 (x)$
  • $\tan (2x) = \frac{2\tan (x)}{1-\tan^2 (x)}$

This article is a stub. Help us out by expanding it.

Proof

Please try to prove it on your own.

See Also

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