WOLFRAM NOTEBOOK

WOLFRAM|DEMONSTRATIONS PROJECT

The Law of Cosines

​
α =
4.47214
β = 4.47214 γ = 4.00000 cos(A) = 0.44721
2
α
=
20.00000
-2βγcos(A)+
2
β
+
2
γ
= 20.00000
The Law of Cosines relates the three side lengths of a triangle with the cosine of one of its angles. If this angle, call it
A
, is formed by sides
β
and
γ
and opposite side
α
, then the law of cosines states that
2
α
=
2
β
+
2
γ
-2βγcosA
. When
A=π/2
, the last term is zero, giving the Pythagorean theorem as a special case.
Wolfram Cloud

You are using a browser not supported by the Wolfram Cloud

Supported browsers include recent versions of Chrome, Edge, Firefox and Safari.


I understand and wish to continue anyway »

You are using a browser not supported by the Wolfram Cloud. Supported browsers include recent versions of Chrome, Edge, Firefox and Safari.