MathDB
distinct points

Source:

July 7, 2013
trigonometry

Problem Statement

The three distinct pointsB,C,D B, C, D are collinear with C between B and D. Another point A not on the line BD is such that AB=AC=CD.|AB| = |AC| = |CD|. Prove that ∠BAC=36BAC = 36 if and only if 1/CD1/BD=1/(CD+BD)1/|CD|-1/|BD|=1/(|CD| + |BD|) .