SOLUTION: 15x^4 - 13x^2 + 2 = 0 Solving equations in quadriatic form please help if you can.

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Question 85629: 15x^4 - 13x^2 + 2 = 0
Solving equations in quadriatic form
please help if you can.
Found 2 solutions by dolly, stanbon:
Answer by dolly(163) About Me  (Show Source):
You can put this solution on YOUR website!

15x^4 - 13x^2 + 2 = 0
15x^4 - 10 x^2 - 3x^2 + 2 = 0
==> 5x^2(3x^2 - 2) -1(3x^2 - 2) = 0
==> (3x^2 - 2) (5x^2 - 1) = 0

==> 3x^2 - 2 = 0 or 5x^2 - 1 = 0
==> x^2 = 2/3 or x^2 = 1/5
x = +/- sqrt(2/3) or x = +/- sqrt(1/5)

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
15x^4 - 13x^2 + 2 = 0
(15x^4 -10x^2 -3x^2 +2) = 0
5x^2(3x^2-2) -(3x^2-2) = 0
(3x^2-2)(5x^2-1) = 0
x^2 = 2/3 or x^2=1/5
x=+-(sqrt6)/3 or x=+-(sqrt5)/5
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Cheers,
Stan H.