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I need help with my pre-calculus homework, could you show me how to solve this inequality in simple steps? The image of the problem is attached.Solving Polynomial InequalitiesDirections: Copy each inequality onto a piece of paper and solve.

I need help with my pre-calculus homework, could you show me how to solve this inequality-example-1
User Seccpur
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1 Answer

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The given inequality is expressed as

(x + 1)(x - 3)^2 ≥ 0

We would replace the inequality symbol with equal to. We have

(x + 1)(x - 3)^2 = 0

This can also be written as

(x + 1)(x - 3)(x - 3) = 0

This means that

x + 1 = 0 or x - 3 = 0 twice

x = - 1 or x = 3 twice

We would substitute values of x to the left and right of these roots into the inequality and check if they satisfy the inequality. Thus,

For x = - 2, we have

(- 2 + 1)(- 2 - 3)^2 ≥ 0

- 1)(-5)^2 ≥ 0

- 5 ≥ 0

We know that this is not true because - 5 is never greater than 0. Thus, values of x below - 1 does not satisfy the inequality

For x = 0, we have

(0 + 1)(0 - 3)^2 ≥ 0

1)(-3)^2 ≥ 0

3 ≥ 0

This is true

For x = 4, we have

(4 + 1)(4 - 3)^2 ≥ 0

5)(1)^2 ≥ 0

5 ≥ 0

This is true

This means that all values of x to the right of - 1 satisfy the inequality. This means that the solutions are between - 1 and infinity. The correct option is the last one. The bracket is used because - 1 is inclusive

[- 1, infinity)

User Jparker
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