f(x) = -x^7+6*x^5-9*x^3

[Maple Plot]

matrix([[`x points above:`, -1.732, -1.516, -1.134, -.7481, 0., .7481, 1.134, 1.516, 1.732], [`a zero of f ?`, __, __, __, __, __, __, __, __, __], [`x-inter of f ?`, __, __, __, __, __, __, __, __, __...