Question

tìm x biết 

(x+3)(x^2-3x+9)-x(x-1)(x+1)=14

Answer 1

(x + 3)(x² - 3x + 9) - x(x - 1)(x + 1) = 14

<=> x³ + 27 - x(x² - 1) = 14

<=> x³ + 27 - x³ + x = 14

<=> x³ - x³ + x = 14 - 27

<=> x = -13

Answer 2

\(\left(x+3\right)\left(x^2-3x+9\right)-x\left(x-1\right)\left(x+1\right)=14\)

\(\Leftrightarrow x^3+27-x^3+x=14\)

hay x=-13

 

Answer 3

(x + 3)(x² - 3x + 9) - x(x - 1)(x + 1) = 14

=> x³ + 27 - x(x² - 1) = 14

=> x³ + 27 - x³ + x = 14

=>  x = 14 - 27

=> x = -13