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Re: st: Why the square of a negative number is still negative

 From Austin Nichols To statalist@hsphsun2.harvard.edu Subject Re: st: Why the square of a negative number is still negative Date Fri, 16 Dec 2011 11:37:19 -0500

```Tiago V. Pereira <tiago.pereira@mbe.bio.br>:
Just order of operations; `x'^2 or -2^2 is the negative of 2 squared
or -4, and if you want (-2)^2 you have to wrap your local in
parentheses.

On Fri, Dec 16, 2011 at 11:31 AM, Tiago V. Pereira
<tiago.pereira@mbe.bio.br> wrote:
> Dear statalisters,
>
> Can someone explain why is this happening?:
>
> local x = -2
> */Approach A:
> dis (`x'^2)*(5)
> */Approach B:
> dis (`x'*`x')*(5)
> */Approach C:
>  dis ((`x')^2)*(5)
>
>
> My output is:
>
> . dis (`x'^2)*(5)
> -20
>
> . */Approach B:
>
> . dis (`x'*`x')*(5)
> 20
>
> . */Approach C:
>
> .  dis ((`x')^2)*(5)
> 20
>
>
> Do I need vacations? (Am I forgetting something very simple from
> mathematics?)
>
> All the best,
>
> Tiago

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