Showing posts with label change of origin. Show all posts
Showing posts with label change of origin. Show all posts

Monday, 13 February 2017

All Cubic Polynomials Are Point Symmetric

It was accident that I stumbled upon this PDF file discussing point symmetry in cubic polynomials. I had been looking for information about sketching cubic polynomials that could help a student I am currently tutoring in Mathematics. I've extracted the key observation in the screen shot below:


Here is an annotated graph that I produced in GeoGebra illustrating the point of symmetry for a specific cubic polynomial: \(\ f(x)=x^3-3x^2+2x-1\)



A translation of the graph (-1, 1) to (0, 0) makes the graph symmetry about the origin and an odd function. The new equation is calculated as follows: \(\ f(x)-1=(x+1)^3-3(x+1)^2+2(x+1)-1\) and \(\ f(x)=x(x+1)(x-1)\) or \(\ f(x)=x(x^2-1)\).