For a triangle with the sides: $a=832, b=623, c=345$ find the angles.

Question

For a triangle with the sides: $a=832, b=623, c=345$ find the angles $A$, $B$ and $C$ which are opposite to lengths sides $a$, $b$ and $c$ as shown below:

Here are the solutions I get on my attempt (in degrees, rounded to whole numbers):

$$ A=116 $$ $$ B=42 $$ $$ C=22 $$

Are they correct?

Answer 1

$$c^2=a^2+b^2-2ab \cos\gamma$$ Transform the equation so that you have the values you know on one side, and cos on the other. Then apply the inverse function of cos.

If you are rounding the exact solutions, I would take 43 for B.