Cosine Law Calculator and Solver
Online calculator, based on the cosine Law , to solve triangle problems. The first calculator solves triangle problems when 3 sides are given (SSS case) and the second calculator solves triangle problems when 2 sides and their included angle are given (SAS case).
The cosine laws are given by:
a 2 = b 2 + c 2 - 2 b c cos(A)
which gives A = arccos [ (b 2 + c 2 - a 2) / 2 b c ]
2) b 2 = a 2 + c 2 - 2 a c cos(B)
which gives B = arccos [ (a 2 + c 2 - b 2) / 2 a c ]
3) c 2 = b 2 + a 2 - 2 b a cos(C)
which gives C = arccos [ (b 2 + a 2 - c 2) / 2 a b ]
1 - Use Cosine Law Calculator when 3 Sides are Given (SSS case)
Enter the 3 sides a, b and c as positive real numbers and press "enter". The outputs are the 3 angles A (opposite side a), B (opposite side b) and C (opposite side c) in DEGREES.
For a triangle to exist, the sum of any two sides must be greater than the third side.
1 - Use Cosine Law Calculator when 2 Sides and the Included Angle are Given (SAS case)
Enter the given angle in A (in DEGREES) and the two sides in b and c as positive real numbers and press "enter". The outputs are side a and 2 angles B (opposite side b) and C (opposite side c) in DEGREES.
More References and Links Online Geometry Calculators and Solvers .
Sine Law Calculator and Solver .
Cosine Law Problems .
Sine Law Problems .
Laws of Sines and Cosines Problems Calculator.