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I need help with this math question.

x^3-8x^2<0

User Andreoss
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1 Answer

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Answer:

(-∞ < x < 0) ∪ (0 < x < 8)

Explanation:

Factoring the inequality gives you ...

x²(x -8) < 0

The x-intercepts of the curve described by the left-side expression are 0 and 8, values that make the factors zero. The intercept at x=0 has multiplicity 2, so the curve does not cross the x-axis there.

Since this is an odd-degree polynomial with a positive leading coefficient, its general shape is rising to the right. That means the left-side expression will be negative for x-values less than the first x-intercept, and for x-values between the x-intercepts.

The solution is ...

(-∞ < x < 0) ∪ (0 < x < 8)

I need help with this math question. x^3-8x^2<0-example-1
User Jagatjyoti
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