Solving a Polynomial: y=x^4/(x^2+1) and y=1/(x^2+1)

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Homework Statement



The curves are:

[tex]y = \frac{x^{4}}{x^{2}+1}[/tex]

and

[tex]y = \frac{1}{x^{2}+1}[/tex]

The Attempt at a Solution



So again I assume that:

[tex]\frac {x^{4}}{x^{2}+1} = \frac {1}{x^{2}+1}[/tex]

and then cross multiply:

[tex](x^{2}+1) = x^{4}(x^{2}+1)[/tex]

not really sure at this point if i should distribute the x^4 but if i do it looks like so:

[tex](x^{2}+1) = (x^{6}+x^{4})[/tex]

so:

[tex](x^{2}+1)-(x^{6}+x^{4}) = 0[/tex]

and I am not really sure what to do at this point, I do have a polynomial if I do the subtraction which is:

[tex]-x^{6}-x^{4}+x^{2}+1 = 0[/tex]

but I don't know how to factor it...

thanks guys!
 
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Asphyxiated said:

Homework Statement



The curves are:

[tex]y = \frac{x^{4}}{x^{2}+1}[/tex]

and

[tex]y = \frac{1}{x^{2}+1}[/tex]


The Attempt at a Solution



So again I assume that:

[tex]\frac {x^{4}}{x^{2}+1} = \frac {1}{x^{2}+1}[/tex]

and then cross multiply:
Don't cross multiply. Multiply both sides by x^2 + 1.
Asphyxiated said:
[tex](x^{2}+1) = x^{4}(x^{2}+1)[/tex]

not really sure at this point if i should distribute the x^4 but if i do it looks like so:

[tex](x^{2}+1) = (x^{6}+x^{4})[/tex]

so:

[tex](x^{2}+1)-(x^{6}+x^{4}) = 0[/tex]

and I am not really sure what to do at this point, I do have a polynomial if I do the subtraction which is:

[tex]-x^{6}-x^{4}+x^{2}+1 = 0[/tex]

but I don't know how to factor it...

thanks guys!
 
thanks man, worked out, but I am having a WAY hard time trying to do this problem so I will post the actual problem another thread. thanks for the help here though.