How to ask "If you have any problem then ask me" in polite manner.
While discussing problem with my brother in chat, he most of the times ask me how you get to the solution and then I have to explain each step. And in between he keep on asking me questions. This was about chat so there is no problem.
Now if I'm writing a mail, what I do is I write the solution to the problem and ask him that 'if you have any problem then ask me'.
He is my brother so he understands but if I do same with with any professor then that will be a trouble for me.
Please help me with some phrases which means "if you have any problem then ask me" but in polite manner.