How do you use the keyboard to insert a square root symbol in Microsoft Word Equation Editor? I know that it can be inserted using the mouse, but I'm using it so frequently that that method (or copying and pasting it from somewhere I've already used it) is cumbersome.
Type in \sqrt x
followed by another space to insert the square root of x. Replace x
with a longer expression in parentheses to insert the square root of that, e.g., \sqrt (x+1)
. Don't forget that space at the end, as that's what extends the square root symbol's horizontal bar over everything and removes the parentheses. Source.
There are several ways you can insert the square root symbol in Microsoft Word. And using the insert equation option is just one of them.
To insert the square root symbol in word, just follow the steps below:
 Place the insertion pointer at where you want to insert the symbol.
 Press Alt+= on your keyboard. These hotkeys will show the equation field.
 Now type \sqrt inside the equation field, then hit the spacebar.
Word will convert the text (\sqrt) into a square root symbol.
Below is a link to a more detailed post on how to insert the square root symbol in Word:
(I can't add comments so I will add an answer.)
As your answer says, it is \sqrt
(followed by space).
In Word 2010 or later, you can easily find these keyboard codes by looking at the Symbols section of the Equation Tools ribbon, finding the symbol, and hovering the mouse over it. The square root symbol appears in the second row.

Certainly easier to find them there than trying to dig up the keyboard codes on the web! – Vincent May 19 '17 at 3:29