As my title says, I need to take only the positive square root of some evaluation. For my calculation, the negative square root is extraneous.(adsbygoogle = window.adsbygoogle || []).push({});

What I do is a normalization of a wave function:

My only problem is those above expression will give me A = {-1/sqrt(2), 1/sqrt(2)}.Code (Text):J = Integrate[Psi[x]^2, {x, 0, a}]

sol = Solve[J == 1, A]

A /. sol

How can I force Mathematica to only give me positive square root?

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# Taking only the positive sqrt in Mathematica

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