Difference between revisions of "Law of Cosines"

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The '''Law of Cosines''' is a formula used in finding lengths and angles of a triangle.  For sides a, b, and c with opposite angles A, B, and C respectively:
 
The '''Law of Cosines''' is a formula used in finding lengths and angles of a triangle.  For sides a, b, and c with opposite angles A, B, and C respectively:
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<math>c^2 = a^2 + b^2 - 2ab\cos C</math>
 
<math>c^2 = a^2 + b^2 - 2ab\cos C</math>
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<math>b^2 = a^2 + c^2 - 2ac\cos B</math>
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<math>a^2 = b^2 + c^2 - 2bc\cos A</math>
  
 
==See also==
 
==See also==

Revision as of 15:23, 29 June 2006

The Law of Cosines is a formula used in finding lengths and angles of a triangle. For sides a, b, and c with opposite angles A, B, and C respectively:

$c^2 = a^2 + b^2 - 2ab\cos C$

$b^2 = a^2 + c^2 - 2ac\cos B$

$a^2 = b^2 + c^2 - 2bc\cos A$

See also

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