How to Solve a Quartic Equation by Hand

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phillyolly
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Hi!

I have been solving a problem and got an equation:
15x^4-30x^2+1=0

Do you know how to solve such equation for x by hand without using sophisticated math tools?
 
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you can assume x^2 = t
so you get a quadratic in t... which i assume you can easily:wink: solve and get two values of t.
using these you will then get 4 values in x(some of which may be rejected according to the problem)
 
This is a great idea! Thank you! ;-)
 

Thread 'Finding the nth roots of a complex number'

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