I have a question about my Mathematics Stack Exchange post: Van Dyke's matching principles
I haven't downvoted you, but I would expect it's because you've provided links to images rather than writing the mathematics out.
The site expects questions to be self-contained, and having to click a link to see your question, then two(!) more links to see your answer is (though it may not seem like it to you) quite a lot of work. At a minimum, someone trying to answer has to have four tabs open -- one for each of your links, plus math.stackexchange -- and has to keep switching between them.
Next but related: by putting everything in a link it becomes very hard to refer to anywhere in your text to point out a mistake or even where you've done something well. You may also find it hard to follow an answer that has to keep saying "line 6 of the second answer link...". If you type it all out, someone can cut'n'paste the relevant section from your question into their answer to explain it.
Lastly: you picked the wrong tag really, though that's not that surprising since you're new here. You want the proof-verification tag since that's what you're asking for. The calculus tag attracts a lot of attention, but (and I may be being a little unfair here, this is entirely my opinion and should be treated as such) it also attracts a lot of people who want to read and quickly answer a question. You may get downvotes because they are annoyed that instead of a question you've posted three links.
I don't think the core of your question is bad at all -- but your presentation isn't helping you, I'm afraid.