27.5 Putting Vectors to Work: Geometry and Physics
Point 4 of 7
27.5.4 Proving the Law of Sines with Vectors
Core idea
Go once around the triangle so the vectors sum to zero, project along the altitude, and you find each side's ratio to the sine is equal.
Module goal. Use vectors as a toolkit to prove geometric theorems, compute lengths and angles, handle forces and velocities, and lay the groundwork for vectors in space.
eastmath.com · 27.5 Putting Vectors to Work: Geometry and Physics · 27.5.4 Proving the Law of Sines with Vectors