How to use law of cosines for SSS

The video tutorial explains how to find the angles of a triangle given its sides using trigonometric laws. It starts by identifying the need to find angles in a side-side-side triangle and choosing the angle opposite the longest side to calculate first. The law of cosines is applied to find angle B, which is obtuse. Then, the law of sines is used to find angle A, and finally, angle C is calculated by subtracting the sum of angles A and B from 180 degrees.

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