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How to use the law of cosines to find out no triangles exist

Learn how to solve for the lengths of the sides and the measures of the angles of a triangle using the law of cosines. The ...
BBC

Higher – Cosine rule

There are two versions of the cosine rule: Find an unknown side using 𝑎² = 𝑏² + 𝑐² – 2𝑏𝑐 cos𝐴 Find an unknown angle using cos𝐴 = \(\frac{𝑏² + 𝑐² – 𝑎²}{2𝑏𝑐}\) Scientific calculators need to ...