help with equation involving x^(3/2)

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mricks152
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help with equation involving x^(3/2)

I need to solve the following equation:

2x^2 + 15x^(3/2) + 155x + 75 = 0

Any ideas?

nona.m.nona
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Re: help with equation involving x^(3/2)

I need to solve the following equation:

2x^2 + 15x^(3/2) + 155x + 75 = 0

Any ideas?
One might try restating the current variable and powers in terms of y = sqrt[x]:

$2\left(\sqrt{x}\right)^4\, +\, 15\left(\sqrt{x}\right)^3\, +\, 155\left(\sqrt{x}\right)^2\, +\, 75\, =\, 0$

$2y^4\, +\, 15y^3\, +\, 155y^2\, +\, 75\, =\, 0$

Then apply standard techniques for solving polynomial equations.

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