Derivative checker

Janet Chen
This applet will try to check whether you've calculated a derivative correctly. Note: Computers are extremely finicky with functions, so there's a chance that the computer will think your answer is incorrect even when it's correct. In that case, take a look at the purple graph, which is the difference between the actual derivative and your derivative; if the purple graph appears to just be 0, that means your derivative is most likely correct, and the computer is just being difficult!
This applet is still experimental, so it may not work perfectly. If the computer doesn't agree with you, check with a real person!