#77 · Trigonometry · Triangles and circles

The sine rule sees the circle

For a triangle with a side $a$ opposite angle $A$ , prove that $\frac{a}{sin A} = 2 R$ , where $R$ is the radius of the triangle's circumscribed circle.

~14 minWritten answer · compare with the solutionInscribed angle theoremCircumcircle

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