Answer :

Sure, let's solve the equation step-by-step.

We need to solve the equation:

[tex]\[ -x^3 - 2x^2 + 8x = 0 \][/tex]

First, we can factor out the common term [tex]\( x \)[/tex] from each term:

[tex]\[ x(-x^2 - 2x + 8) = 0 \][/tex]

This gives us one solution immediately:

[tex]\[ x = 0 \][/tex]

Next, we need to solve the quadratic equation inside the parentheses:

[tex]\[ -x^2 - 2x + 8 = 0 \][/tex]

To make it a bit simpler, let's multiply the entire equation by [tex]\(-1\)[/tex]:

[tex]\[ x^2 + 2x - 8 = 0 \][/tex]

Now, we solve this quadratic equation using the quadratic formula, which is given by:

[tex]\[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \][/tex]

For our equation [tex]\( x^2 + 2x - 8 = 0 \)[/tex], the coefficients are:
- [tex]\( a = 1 \)[/tex]
- [tex]\( b = 2 \)[/tex]
- [tex]\( c = -8 \)[/tex]

Substituting these values into the quadratic formula, we get:

[tex]\[ x = \frac{-2 \pm \sqrt{2^2 - 4 \cdot 1 \cdot (-8)}}{2 \cdot 1} \][/tex]

Simplify inside the square root:

[tex]\[ x = \frac{-2 \pm \sqrt{4 + 32}}{2} \][/tex]
[tex]\[ x = \frac{-2 \pm \sqrt{36}}{2} \][/tex]
[tex]\[ x = \frac{-2 \pm 6}{2} \][/tex]

This gives us two solutions:

[tex]\[ x = \frac{-2 + 6}{2} = \frac{4}{2} = 2 \][/tex]

[tex]\[ x = \frac{-2 - 6}{2} = \frac{-8}{2} = -4 \][/tex]

So, the solutions to the equation are:

[tex]\[ x = -4, \quad x = 0, \quad x = 2 \][/tex]

Therefore, the solutions are:

[tex]\[ x = [-4, 0, 2] \][/tex]

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