Question

Use the law of cosines to find the value of 2, 3, 4 cos (theta).

Answer 1

\[c^2 = a^2 + b^2 - 2ab \cos \theta\]
a = 3
b = 4
c = 2

Answer 2

Would that be like this: http://www.wolframalpha.com/input/?i=2%5E2%3D3%5E2%2B4%5E2-2%2812%29cos%28theta%29