CAS Example: Proof of the Midpoint-Tangent for a Cubic
- Author:
- Michael Borcherds
- Topic:
- Tangent Line or Tangent
A=(a,0)
B=(B,0)
C=(c,0)
A cubic has roots a, b, c. The tangent at D (with x-coordinate (a+b)/2) will always pass through C.
This is a proof, and an interactive demonstration.