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Penta-Quadratic (Posted on 2014-02-23)

Let x be a non-zero real number such that (x³+20x)^1/5=(x⁵-20x)^1/3. Find the product of all possible values of x.

No Solution Yet Submitted by Danish Ahmed Khan

Rating: 4.0000 (1 votes)

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re(2): A long way ----=0.0024990669i ??

| Comment 4 of 5 |

(In reply to re: A long way ----=0.0024990669i ?? by Ady TZIDON)

I did not mean that this was a solution to the equation in the problem. Which, as you pointed out, cannot have more than 5.

It was an extraneous solution that somehow arose when I raised to the 15th power and got a 25th degree polynomial.

Posted by Jer on 2014-03-06 11:25:22

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