Math & Statistics
Law of Cosines Calculator
Find the third side of a triangle given two sides and the included angle.
Your inputs
Change any value to update the result instantly.
Side c
7.2111
Angle A
73.8979 °
Angle B
46.1021 °
Formula and working
c² = a² + b² − 2ab·cos(C)
- 1
Collect the inputs
Side a = 8; Side b = 6; Included angle C = 60 °
- 2
Apply the formula
c² = a² + b² − 2ab·cos(C)
- 3
Result
Side c = 7.2111
Frequently asked questions
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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