Hey guys, I just have quick question:

How does $\displaystyle \frac{\sqrt{9x^2+x}}{x} = \sqrt{9+1/x}$ knowing that $\displaystyle \sqrt{x^2} = x$

big thanks.(Happy)

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- Mar 13th 2011, 10:56 PMhydrideHow does sqrt(x^2) = 1?
Hey guys, I just have quick question:

How does $\displaystyle \frac{\sqrt{9x^2+x}}{x} = \sqrt{9+1/x}$ knowing that $\displaystyle \sqrt{x^2} = x$

big thanks.(Happy) - Mar 13th 2011, 11:25 PMProve It
Assuming that $\displaystyle \displaystyle x \geq 0$, then $\displaystyle \displaystyle \sqrt{x^2} = x$.

Since $\displaystyle \displaystyle \frac{\sqrt{9x^2 + x}}{x} = \frac{\sqrt{9x^2 + x}}{\sqrt{x^2}}$

$\displaystyle \displaystyle = \sqrt{\frac{9x^2 + x}{x^2}}$.

Go from here. - Mar 13th 2011, 11:46 PMhydride
Thank you! I got it.