Cosine Rule – Missing Angle
How to use this applet:
- Click the "Generate Triangle" button to get a new triangle with two angles and one side.
- Determine the missing angle using the Cosine Rule.
- Check your answer by toggling the "Show solution" checkbox.
1
Click the button to generate a random triangle
2
Apply the cosine rule
\( \cos(C) = \frac{a^2 + b^2 - c^2}{2ab} \)
Side c = ? units