Solve by Factoring 9x^3-9x=0

$9 x^{3} - 9 x = 0$

Step 1

Factor $9 x$ out of $9 x^{3} - 9 x$ .

Factor $9 x$ out of $9 x^{3}$ .

$9 x (x^{2}) - 9 x = 0$

Factor $9 x$ out of $- 9 x$ .

$9 x (x^{2}) + 9 x (- 1) = 0$

Factor $9 x$ out of $9 x (x^{2}) + 9 x (- 1)$ .

$9 x (x^{2} - 1) = 0$

Step 2

Rewrite $1$ as $1^{2}$ .

$9 x (x^{2} - 1^{2}) = 0$

Step 3

Factor.

Since both terms are perfect squares, factor using the difference of squares formula, $a^{2} - b^{2} = (a + b) (a - b)$ where $a = x$ and $b = 1$ .

$9 x ((x + 1) (x - 1)) = 0$

Remove unnecessary parentheses.

$9 x (x + 1) (x - 1) = 0$

Step 4

If any individual factor on the left side of the equation is equal to $0$ , the entire expression will be equal to $0$ .

$x = 0$

$x + 1 = 0$

$x - 1 = 0$

Step 5

Set $x$ equal to $0$ .

$x = 0$

Step 6

Set $x + 1$ equal to $0$ and solve for $x$ .

Set $x + 1$ equal to $0$ .

$x + 1 = 0$

Subtract $1$ from both sides of the equation.

$x = - 1$

Step 7

Set $x - 1$ equal to $0$ and solve for $x$ .

Set $x - 1$ equal to $0$ .

$x - 1 = 0$

Add $1$ to both sides of the equation.

$x = 1$

Step 8

The final solution is all the values that make $9 x (x + 1) (x - 1) = 0$ true.

$x = 0, - 1, 1$