Check My Answer CalcLens

Did you get it right? Type the problem and your answer. This page does not look your answer up — it differentiates it and checks whether the result matches, which is the same thing you can do on paper.

Leave the off — any constant is accepted, because every antiderivative is correct up to one.

Check My Answer

Pick Antiderivative or Derivative, type the problem, type your answer, and press Check it.

How the check actually works

For an antiderivative, the page differentiates your answer and compares it to the integrand at a spread of x values. If the two agree everywhere they are tested, your answer is right. This is exactly the check you should do by hand — an antiderivative is verified by differentiating it, and that direction is always the easy one.

Because the comparison is numeric, your answer does not have to look like anyone else's. and both pass, and so does any answer that differs by a constant.

Reading a "no"

When the answer is wrong, the page names one x where the two disagree and shows both values. Substituting that number back into your work is usually the fastest way to find the slip.

Two curves are also drawn. If your answer is right they sit exactly on top of each other; where they peel apart is where the error is.

What it will not do

Show me one gives a correct answer when the problem is inside Calculus 1's standard catalogue. Some integrals have no elementary antiderivative at all, and the page says so rather than inventing one — but your answer can still be checked either way.