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Solve when the following function is below zero using the Algebraic method

g(x) = -1/6(x+3)^3(x-(3/2))(x-2)^2

User Kuyenda
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Answer:


(-\infty, -3) \cup \left((3)/(2), 2\right) \cup (2, \infty)

Explanation:

Given function:


g(x) = -(1)/(6)(x+3)^3\left(x-(3)/(2)\right)(x-2)^2

To solve the inequality g(x) < 0 for the given continuous function g(x), begin by finding the roots of the polynomial by setting each factor equal to zero and solving for x:


x + 3 = 0 \implies x = -3


x - (3)/(2)= 0 \implies x = (3)/(2)


x - 2 = 0 \implies x = 2

We need to consider the intervals between and beyond the found roots.

In this case, we have four intervals: (-∞, -3), (-3, 3/2), (3/2, 2), and (2, ∞).

Choose a value within each interval and substitute it into the function g(x), then determine whether the resulting value is positive or negative.

For the interval (-∞, -3), use x = 4:


g(-4) = -(1)/(6)((-4)+3)^3\left((-4)-(3)/(2)\right)((-4)-2)^2 = -33 < 0

For the interval (-3, 3/2), use x = 0:


g(0) = -(1)/(6)(0+3)^3\left(0-(3)/(2)\right)(0-2)^2 = 27 > 0

For the interval (3/2, 2), use x = 7/4:


g(1.75) = -(1)/(6)\left((7)/(4)+3\right)^3\left((7)/(4)-(3)/(2)\right)\left((7)/(4)-2\right)^2 =-0.279... < 0

For the interval (2, ∞), use x = 3:


g(3) = -(1)/(6)(3+3)^3\left(3-(3)/(2)\right)(3-2)^2 = -54 < 0

From the above calculations, we can conclude that g(x) is below zero (negative) in the intervals (-∞, -3), (3/2, 2) and (2, ∞).

Therefore, the solution to the inequality g(x) < 0 is:

  • (-∞, -3) ∪ (3/2, 2) ∪ (2, ∞)

(This solution assumes that there are no additional factors or constraints on the domain of the function g(x)).

Solve when the following function is below zero using the Algebraic method g(x) = -1/6(x-example-1
User Patfreeze
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