Yes, answer the question, you are encouraged to answer your own question, how simple it is, is irreverent, you can even accept your own answer (though you don't get the +15 rep).
Many people overlook things and we have all asked questions like this, it seems reasonable, to me, that if you overlooked this, then others may too but don't write anything like " don't be stupid.", keep it professional.
There is no need for you to come back and delete it, it will be fine.