Where do variables outside of a square root go?

Question

This is a formatting question. Example, $\sqrt{4}x^2 \text{ or } x^2\sqrt{4}$. Which is less ambiguous? Is there a style guideline for things like this?

Clearly one should write $2x^2$. – Pedro Sep 30 '13 at 23:38 — Pedro, Sep 30 '13 at 23:38

score 6 · Accepted Answer · answered Sep 30 '13 at 23:36

6

Particularly when writing by hand, I prefer $x^2\sqrt 4$. It avoids the worry that the top bar of the square root sign might extend over the $x^2$ and make you think it is inside. Even when typeset, it keeps people from worrying that you forgot some braces and the $x^2$ belongs inside.

answered Sep 30 '13 at 23:36

Ross Millikan

374,822

I always write something like $\large\tt\mbox{,\sqrt{4,},}$ when I use $\large\tt LaTeX$. Indeed, I define another one which is based in the above scheme. – Felix Marin Sep 30 '13 at 23:39
$\large\tt\mbox{\newcommand{\root}[2][]{,\sqrt[#1]{#2,},}}$ – Felix Marin Sep 30 '13 at 23:43

score 6 · Answer 2 · answered Sep 30 '13 at 23:42

6

Also, this is a good occasion to use a TeX "\cdot", as in $\sqrt{4}\cdot x$. It is true that writing "$x^2\,\sqrt{4}$" disambiguates, but to me it looks very strange, definitely stranger than having the "\cdot" inserted. I've gotten into the habit of using more "cdots" in handwritten things since "discovering" the TeX use. Tastes vary...

answered Sep 30 '13 at 23:42

paul garrett

52,465

1

I also prefer the numerical part on the left. Another option is to "close" the root. (+1) – user26872 Oct 01 '13 at 02:29

score 1 · Answer 3 · answered Sep 30 '13 at 23:45

1

The numerical coefficient is usually put before the variable. I would go for $(\sqrt{4})x^2$.

answered Sep 30 '13 at 23:45

JRN

6,566

Where do variables outside of a square root go?

3 Answers3