I have just logged in on math.stack and I immediately see
Can you guys please provide the answer? [closed]
and then I clicked and I realized that OP asked the question 5 minutes ago
see
Is that ok ?
OP is a new contributor that does not even know how to use MathJax, by judging the question seems like is a first year student (remember how lost one is in the first years) and by looking at his name (Japanese name) seems like it is not a native english speaker.
Note: Don't read my question like a rant (which means speak or shout at length in a wild, impassioned way) that was not the tone when I was writing it. Had I used mark like this one !!!! or ??? or other kind of comments, that'd have been different.