Can you find all real zeros of the function f(x) = x^3-8x^2+11x+20?

Answer 1

f(x) = x³ - 8x² + 11x + 20

This cubic equation factors. You want three numbers that multiply to give 20 (the constant term) and add to give -8 (coefficient of the x² term). The answers are -5, -4, and +1:

1. (-5)(-4)(1) = 20
2. -5 + (-4) + 1 = -8

So f(x) = (x-5)(x-4)(x+1) and the zeros are x = 5, 4, and -1.