## anonymous 4 years ago Could someone explain how 4 + x^4 - 2 + (1/x^4) is equal to (x^2 + 1/(x^2))^2 please?

1. anonymous

is the first part really $4+x^4-2$??

2. anonymous

yes, + 1/(x^4)

3. anonymous

so first part is really $2+x^4$ and you have $2+x^4+\frac{1}{x^4}$

4. anonymous

then to add you have a denominator of $x^4$ so you need to write $\frac{2x^4}{x^4}+\frac{x^8}{x^4}+\frac{1}{x^4}$ $\frac{x^8+2x^4+1}{x^4}$ $\frac{(x^4+1)^2}{x^4}$ or $\left( \frac{x^4+1}{x^2}\right)^2$

5. anonymous

Oh! Thanks! :)