Cupid, if you need to put a maths sign of any kind into, say. a word document, look for 'insert > symbol' - on my old version of word its a drop-down top left of screen but on newer versions it will be under the tab marked 'insert'.
In this option you'll find anything you want.
I find this a very handy option, when preparing notes for lessons that require , say. 'degrees' (the little circle'), or a foreign letter like a german o with an umlaut over it.