Question

x³ - 2x² - x + 2 = 0

Answer 1

Ответ:

$x^{3}-2x^{2} -x+2=0\\ x^{2} (x-2)-(x-2)=0\\(x-2)(x^{2} -1)=0\\x-2=0\\x^{2} -1=0\\x_{1} =2\\x_{2} = -1\\x_{3} =1$