Find x^3 - 2x + 1 when

Question

x² - × - 1 = 0

 

Answer 1

x^2 -x + 1/4 = -1 + 1/4 = -3/4

(x-1/2)^2 = -3/4

x = 1/2 + or - (i/2)sqr3. plug those values into the cubic equation. You'll get another imaginary number