AS/A2 Pure 2 Pure 3

P1 Topic 2: Algebra
P1.2
Show that, for all real values of k, the roots of the quadratic equation x2-(2+k)x-3=0 are real. Show further that the roots are of opposite sign. Now prove your answers on paper.

y = x2-(2+k)x-3=0

Summary This problem is adapted from "Exploring Maths with Computers" by Aydin Önaç, The Chase, Malvern Based on free Java applets from JavaMath