96

I'd like to have output an equals sign that has a small question mark over the top of it. (I'm proving an equation, but it is not obvious until the final step that the equation is true.)

Do I need to create a special symbol myself (via a macro, etc.), or is there already one defined?

5
  • 1
    See Typeset an = with an ! above.
    – Caramdir
    Jan 20 '11 at 5:02
  • @Caramdir: I'm voting to close as duplicate. Jan 20 '11 at 7:08
  • 2
    That's only a duplicate if you already know that the answer is "set one above the other yourself".
    – OJFord
    Oct 31 '16 at 20:09
  • This is Unicode U+225F, and with the unicode-math package, a sutable font, and XeLaTeX or LuaLaTeX can be accessed as \questeq. Nov 1 '19 at 23:35
  • @krlmlr below is correct that the solution from the duplicate/linked question is better. To save time for those who Googled to get here (like me), the solution from the linked question uses amsmath and then, within the math environment, the following command: a\overset{?}{=} b.
    – shiri
    Jun 24 at 10:08
144

Use the following command within the math environment ($ <command> $):

\stackrel{?}{=}.

4
  • 7
    On point. Nothing more, nothing less. I define \newcommand{\?}{\stackrel{?}{=}} to make things go faster.
    – Jimi Oke
    Jan 20 '11 at 4:52
  • @jimi- it gave an error, ! Missing $ inserted. <inserted text> $ l.5 \?
    – Aku
    Jan 20 '11 at 15:36
  • 1
    @Aku: It has to be used within the math environment for it to work and that's where I assumed you were working, anyway ;) If you typed $ l.5 \?, then I think you're simply missing the closing $ symbol! Otherwise, it should work fine.
    – Jimi Oke
    Jan 20 '11 at 17:47
  • 15
    Note that the linked question mentions \overset from amsmath which is preferable over \stackrel according to Philippe Goutet. Care to edit your reply? (I googled for "question mark over equals sign" and hence don't think the question should be closed as duplicate ;-) )
    – krlmlr
    Apr 10 '12 at 14:32

Not the answer you're looking for? Browse other questions tagged or ask your own question.