Question

Tìm x,biết:

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

Answer 1

\(\left(x+1\right)\left(x^2-x+1\right)-x\left(x^2-3\right)=4\\ \Leftrightarrow x^3+1-x^3+3x=4\\ \Leftrightarrow3x=1-4=-3\\ \Leftrightarrow x=-3:3=-1\)

Answer 2

(x + 1) (x² - x + 1) - x (x² - 3) = 4

= x³ + 1 - x³ + 3x => 4

= 3x = 1 - 4 => -3

= x = -3 : 3 = -1