SOLUTION: x^4-4x^2+3=0

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Question 305371: x^4-4x^2+3=0
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Let u=x%5E2, then u%5E2=x%5E4
x%5E4-4x%5E2-3=u%5E2-4u%2B3=0
Factor
%28u-1%29%28u-3%29=0
Two u solutions:
u-1=0
u=1
x%5E2=1
x=1 and x=-1
.
.
.
u-3=0
u=3
x%5E2=3
x=sqrt%283%29 and x=-sqrt%283%29
Four x solutions:
(-sqrt%283%29,-1,1,sqrt%283%29)