Cosine rule is also called law of cosines or Cosine Formula. Suppose, a, b and c are lengths of the side of a triangle ABC, then; a2 = b2 + c2 – 2bc cos ∠x. b2 = a2 + c2 – 2ac cos ∠y.
Start by writing out the Cosine Rule formula for finding angles: cos(A), = b2 + c2 – a2. 2bc. Step 2, Fill in the values you know, and the unknown length: cos(P ...
The formula for law of cosines is given as,. a2 = b2 + c2 - 2bc·cosA; b2 = c2 + a2 - 2ca·cosB; c2 = a2 + b2 - 2ab·cosC. where, A, B, and C are the vertices of a ...