Trigonometry
Solving triangles
Laws of sines and cosines, areas, radii and angles.
Trigonometry
Triangle side from two sides and angle
c = √(a²+b²−2ab cos C)→TrigonometryTriangle angle from three sides
C = arccos((a²+b²−c²)/(2ab))→TrigonometryTriangle side using law of sines
b = a sin B / sin A→TrigonometryTriangle area from two sides and angle
S = ab sin C / 2→TrigonometryTriangle third angle
C = 180° − A − B→TrigonometryTriangle circumradius from side and angle
R = a/(2sin A)→TrigonometryTriangle inradius from area and perimeter
r = 2S/P→TrigonometryTriangle height from area and base
h = 2S/a→TrigonometryTriangle area from three sides
S = √(p(p−a)(p−b)(p−c))→