Note: I was initially planning on posting this on Physics.SE, but it is likely relevent to multiple Stack Exchange Sites. Because of this, I will be using examples relevant to the specific case, which was for physics.
As a college student, my professors (usually math or physics professors) will post practice exams in Blackboard, where the students can post answers in the form of comments. What is frustrating about this setup is the lack of formatting, such as Markdown and LaTex. A typical answer will look something like this (this whole thing is an actual comment copied verbatim):
b) To find the radiative electric field, we must first find the perpendicular acceleration. I subtracted 90 degrees from the given angle to obtain an angle between the acceleration vector and the horizontal axis.
/_ <---- it'll look sort of like that
Generally, I get the sense that many of the practice problems posted, would be considered on topic their various subjects' Stack Exchange sites. Currently, all Stack Exchange sites allow for the ability to ask and answer the same question simultaneously, so obviously as a general rule answering your own question is acceptable and even encouraged. What concerns me though, is that these questions will be written in exactly the same form as they are on the test.
For example, someone might post this:
The reason would be so that those in the class could recognize that it's the same question, and allow it to be linked to in the comments. In theory, the idea would be that the original poster also posts an answer to go along with the question. The point of this would be for someone to answer a class question publicly, allowing them to share the process they used to solve it. This makes it different from the typical "I don't feel like doing my homework, maybe I'll just post it on Stack Exchange" that often seems to occur in homework questions, because it would require the OP to already know and be willing to write out the answer to a question that they themselves were theoretically too lazy to solve. If the user writes up the answer as well, it ensures that these types of questions can't be used for a "homework service." Additionally, the answer could serve as the "post what you've tried" part of the question.
I downvote lazy homework questions when I see them as well, but this would seem to me to have a far more legitimate purpose.
Is it ok to ask questions this way, in order to post the answer along with it? Should it involve a special tag, something like student-collaboration? Or is it widely considered frowned upon?