When A + B + C = pi: (1) tanA + tanB + tanC = tanAtanBtanC, (2) sin2A + sin2B + sin2C = 4sinAsinBsinC, (3) cos2A + cos2B + cos2C = -1 - 4cosAcosBcosC. These follow from C = pi - A - B and compound angle expansion. Always try substituting C = pi - A - B first.
Part of TRIG-01 — Trigonometric Ratios, Identities & Equations
Conditional Identities (A + B + C = pi)
Like these notes? Save your own copy and start studying with NoteTube's AI tools.
Sign up free to clone these notes