Question 1

How do I use the Cosine Rule Calculator?

Accepted Answer

The Cosine Rule relates the lengths of the sides of a triangle to the cosine of one of its angles. It is a generalization of Pythagoras' Theorem. Simply enter the known values in the fields provided, and the calculator will solve for the missing ones instantly using the formula: a^2 = b^2 + c^2 - 2bc \cos A.

Question 2

What is the formula for the Cosine Rule?

Accepted Answer

The formula is: a^2 = b^2 + c^2 - 2bc \cos A.

Simple Units

Cosine Rule Calculator

Cosine Rule

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