Trigonify

Law of Cosines

For angle A

cos⁡A=b2+c2−a22bc\cos A = \dfrac{b^{2} + c^{2} - a^{2}}{2bc}
oblique

Related Law of Cosines identities

For side a

Study this and 44 more identities in the Trigonify workspace — an interactive unit circle, a step-by-step triangle solver, quizzes, and a practice problem bank.