Law of Cosines Calculator

MATH CALCULATOR Law of Cosines Calculator Calculate angles and sides of triangles using the Law of Cosines formula.
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What is the Law of Cosines Calculator & How does it work?
The Law of Cosines is a fundamental theorem in trigonometry that relates the lengths of the sides of a triangle to the cosine of one of its angles. It is particularly useful for solving triangles when you know two sides and the included angle, or three sides of the triangle.
The formula for the Law of Cosines is:
c^2 = a^2 + b^2 – 2ab cos(C)
a = length of side A
b = length of side B
C = angle between sides A and B
c = length of side C

This formula can be rearranged to solve for any unknown side or angle in a triangle.
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Frequently Asked Questions
How do I use the Law of Cosines Calculator?
Enter the lengths of two sides and the included angle to find the third side, or input all three sides to determine an angle.
What is the Law of Cosines formula?
The formula is c^2 = a^2 + b^2 – 2ab cos(C), where C is the angle between sides A and B, and c is the side opposite angle C.
When should I use the Law of Cosines?
Use it when you know two sides and the included angle, or all three sides of a triangle to find missing measurements.
Can the Law of Cosines be used for right triangles?
Yes, but for right triangles, using the Pythagorean theorem is simpler. The Law of Cosines still works but is more complex than necessary.
What does cos(C) represent in the formula?
cos(C) represents the cosine of angle C, which is the angle between sides A and B in the triangle.
How do I find the cosine of an angle if it’s not given?
Use a calculator or trigonometric tables to find the cosine value for the given angle.
What are some real-world applications of the Law of Cosines?
It is used in navigation, engineering, architecture, and any field requiring precise triangle measurements.

Results are for informational purposes only and do not constitute professional advice.