11: The Law of Sines and The Law of Cosines
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- 41333
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Previously, we used the fundamental trigonometric relationships in right triangles to find unknown distances and angles. Unfortunately, in many problem solving situations, it is inconvenient to use right triangle relationships. Therefore, from the right triangle relationships, we can derive relationships that can be used in any triangle.
Thumbnail: Law of cosines with acute angles. (CC BY SA 3.0 Unported; Scaler via Wikipedia)