# how to find an angle using law of cosines

## Best answer

Law of Cosines for Angles A, B, and C: If you know three sides of a triangle then you can use the cosine rule to find the angles of a triangle. So, the solving formula for the angles which are used by the law of cosines formula is:A = cos鈭?[ b2 +c2 鈭抋2 2bc] A = c o s 鈭?1 [ b 2 +c 2 鈭?a 2 2 b c]

## People also ask

### What is the law of cosines for angles A B C?

Law of Cosines for Angles A, B, and C: If you know three sides of a triangle then you can use the cosine rule to find the angles of a triangle. So, the solving formula for the angles which are used by the law of cosines formula is: A = cos鈭?[ b2 +c2 鈭抋2 2bc] A = c o s 鈭?1 [ b 2 + c 2 鈭?a 2 2 b c]

### How do you find the unknown angles using cosine law?

The formula to find the unknown angles using cosine law is given by: cos 伪 = [b 2 + c 2 鈥?a 2 ]/2bc cos 尾 = [a 2 + c 2 鈥?b 2 ]/2ac cos 纬 = [b 2 + a 2 鈥?c 2 ]/2ab

### How do you use the law of cosines to find length?

In the last lesson we used the Law of Cosines to find the length of the third side of a triangle when you know the length of two sides and the angle in between. This law can also be used to find the measure of an angle when the three sides of a triangle are given. 1.

### How does the law of cosines work for right triangles?

Remember that the Law of Cosines works for any triangle, not just right triangles. In the last lesson we used the Law of Cosines to find the length of the third side of a triangle when you know the length of two sides and the angle in between. This law can also be used to find the measure of an angle when the three sides of a triangle are given. 1.