The Spherical Law of Cosines is a formula used in spherical geometry to relate the angles and sides of a spherical triangle. It states that for any spherical triangle with sides a, b, and c opposite to angles A, B, and C respectively, the relationship can be expressed as: \[ \cos(a) = \cos(b) \cdot \cos(c) + \sin(b) \cdot \sin(c) \cdot \cos(A) \] This law is particularly useful in fields like navigation and astronomy, where calculations on the surface of a sphere, such as the Earth, are necessary. The Spherical Law of Cosines helps determine unknown angles or sides when given sufficient information about a spherical triangle. It is an essential tool for solving problems involving spherical triangles, which differ from planar triangles due to the curvature of the sphere.