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

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Homework Statement



The curves are:

y = \frac{x^{4}}{x^{2}+1}

and

y = \frac{1}{x^{2}+1}

The Attempt at a Solution



So again I assume that:

\frac {x^{4}}{x^{2}+1} = \frac {1}{x^{2}+1}

and then cross multiply:

(x^{2}+1) = x^{4}(x^{2}+1)

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

(x^{2}+1) = (x^{6}+x^{4})

so:

(x^{2}+1)-(x^{6}+x^{4}) = 0

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

-x^{6}-x^{4}+x^{2}+1 = 0

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

thanks guys!
 
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Asphyxiated said:

Homework Statement



The curves are:

y = \frac{x^{4}}{x^{2}+1}

and

y = \frac{1}{x^{2}+1}


The Attempt at a Solution



So again I assume that:

\frac {x^{4}}{x^{2}+1} = \frac {1}{x^{2}+1}

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

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

(x^{2}+1) = (x^{6}+x^{4})

so:

(x^{2}+1)-(x^{6}+x^{4}) = 0

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

-x^{6}-x^{4}+x^{2}+1 = 0

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.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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