The general guidance here is, "answer the question posed by the OP, but also leave something of value here for the site." What does that mean? Well, if the OP asks for a result, e.g., "What is the value of this integral?", then it is theoretically legit to answer with output from a CAS or Wolfram Alpha. Such an answer may be useful to the OP.
That said, is such an answer useful to the site? No, never. That's right: never. Anyone whose brain hasn't lost oxygen in the past 10 minutes can provide such an answer. That is, unless the OP is asking specifically for such an answer - and usually in such a case, the OP really is asking a question about software, not math, and as such has no place here.
In contrast, what this site needs are people who can clearly provide insight into methods by which such answers are discovered. There is nothing like summarizing steps painstakingly derived using pencil and paper for an answer here. By all means, defer to the OP as to the way (s)he is seeking to do the problem. But in the absence of such a specified technique, do out the problem in the way you are best equipped to explain. Someone here will appreciate it.