If a triangle has sides a, b, and c with opposite angles A, B, and C, what formula states that c^2 = a^2 + b^2 - 2ab cos(C)?
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Law of Cosines
The Law of Cosines is a generalization of the Pythagorean Theorem that applies to all triangles, not just right triangles. It is particularly useful for solving SSS (side-side-side) or SAS (side-angle-side) cases.
Also asked as:
- What trigonometric law is defined by the equation c^2 = a^2 + b^2 - 2ab cos(C)?