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$$\sqrt{r^2 e^{4 \gamma (r)-4 \psi (r)}}$$

If I set

var = r^2*E^(4 \[Gamma][r] - 4 \[Psi][r])

Simplify[Sqrt[var], var > 0]

I just get

$$\left| r\right| \sqrt{e^{4 \gamma (r)-4 \psi (r)}}$$

How to tell Mathematica to perform the full square root calculation?

$$r e^{2 \gamma (r)-2 \psi (r)}$$

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  • 3
    $\begingroup$ ya r has been taken...simple mathematical rule Simplify[Sqrt[(r^2)*E^(4 \[Gamma][r] - 4 \[Psi][r])]]//PowerExpand $\endgroup$ – Rorschach Jul 5 '13 at 19:24
  • $\begingroup$ Thank you! Why does it work? $\endgroup$ – Giovanni F. Jul 5 '13 at 19:32
  • $\begingroup$ Your concern is code snippet or 'r' ? $\endgroup$ – Rorschach Jul 5 '13 at 19:33
  • $\begingroup$ My concern is to get rid of the square root. $\endgroup$ – Giovanni F. Jul 5 '13 at 19:35
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    $\begingroup$ Use e.g. Simplify[ Sqrt[var], r \[Element] Reals && (4 \[Gamma][r] - 4 \[Psi][r]) \[Element] Reals] $\endgroup$ – Artes Jul 5 '13 at 19:51