Need help solving/graphing some inequalities

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    Inequalities
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The discussion focuses on solving and graphing inequalities, specifically the expressions involving absolute values and polynomial inequalities. For the inequality 0 < |x + 3| < 1, the correct solution is identified as -4 < x < -2 or -3 < x < -2, which is confirmed through graphing. The second set of inequalities, 1 ≤ |X - 4| ≤ 3 and 1 ≤ |Y - 4| ≤ 3, leads to the solution ranges 1 ≤ X ≤ 3 or 5 ≤ X ≤ 7, and similarly for Y. The more complex inequality X^3 + 2x^2 > 3X + 6 requires solving the associated equation, revealing roots at -2, -√3, and √3, which help determine the sign of the polynomial across different intervals. Understanding these intervals is crucial for identifying where the original inequality holds true.
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Alright again I am having trouble with a few problems.

I am unsure on the first two problem's answers and I have no idea how to do the third one..Solve and graph the solution on a number line

0 < |x + 3| < 1

I get: -3 < X < -2 or -3 > X > -4

and it graphs like this (is this right?) [horrible picture sorry]

a47sds.png



Graph the solution set on a coordinate of axes
(I know how to graph it I am just unsure on the points)

1 ≤ |X - 4| ≤ 3

1 ≤ |Y - 4| ≤ 3

I ended up getting

5 ≤ Y ≤ 7 or 3 ≥ Y ≥ 1

and the same for X

5 ≤ X ≤ 7 or 3 ≥ X ≥ 1

Is that right? =/

Ok and this last one I have no idea how to solve :confused:

Solve: X^3 + 2x^2 > 3X + 6
 
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Ok I think I have the first two figured out but I am still stuck on

Solve: X^3 + 2x^2 > 3X + 6
 
The best way to solve any complicated inequality is to first solve the associated equation.

x3+ 2x2> 3x+ 6 is the same as x3+ 2x2- 3x- 6> 0 and the associated equationj is x3+ 2x2- 3x- 6= 0.

If there are any rational solutions to that they must divide 6 and so are 1, -1, 2, -2, 3, -3, 6, or -6. Trying each of those we see that (-2)3+ 2(-2)2- 3(-2)- 6= -8+ 8+ 6- 6= 0 so x= -2 is a root. Dividing by (x+ 2) we get x2- 3 as quotient and x= \pm\sqrt{3} as the other 2 roots. The numbers, -2, -\sqrt{3}, and \sqrt{3} separate all real numbers into four intervals: x< -2, -2&lt; x&lt; -\sqrt{3}, -\sqrt{3}&lt;\sqrt{3}, and \sqrt{3}&lt; x. Since the polynomial x3+ 2x2- 3x- 6 is continuous it can change sign only at those points where it is 0. Check on point in each interval to determine whether the numbers in that interval make the value positive or negative.
 
I tried to combine those 2 formulas but it didn't work. I tried using another case where there are 2 red balls and 2 blue balls only so when combining the formula I got ##\frac{(4-1)!}{2!2!}=\frac{3}{2}## which does not make sense. Is there any formula to calculate cyclic permutation of identical objects or I have to do it by listing all the possibilities? Thanks
Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks
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