(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Find an integercsuch that the equation 4x^3 + cx - 27 = 0 has a double root.

2. Relevant equations

Ax^3+Bx^2+Cx+K = 0

Sum of Roots = -B/A

Product of Roots = (-1)^n * k/a

etc.

3. The attempt at a solution

I tried using P/Q with synthetic division to find a quadratic for the problem but I couldn't find a way to get rid of or solve for C.

I also tried manipulating the Sum of Roots and Product of Roots (both listed above) relationships to try and solve for C. No success here.

I have a hunch that it has to deal with the Sum of Roots & Product of Roots relationships, since I know what A is (leading coefficient) and I know what K is (-27, given).

I just can't seem to put it together.

The answer of the problem is C = -27, however I would like to knowhowto get this.

Thank you very much.

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# Homework Help: Finding the Roots of Cubic

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