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Law of Cosines

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

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

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

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

See also

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