How it is calculated
Angle A lies opposite side a. The three angles add up to 180°.
cos A = (b² + c² − a²) / (2bc)
Where the numbers come from
- Side a
- Side b
- Side c
Example
Sides of 3, 4, and 5 give a right angle opposite the side of 5, and angles of about 36,87° and 53,13°.
Questions
Why does it say there is no triangle?
The sum of two sides must be strictly greater than the third.
Angles in radians?
No, the screen shows degrees.
Can you see that it is a right triangle?
An angle of about 90° opposite the longest side in the 3-4-5 example.