As for manipulating the string itself, that is indeed very tricky, and is quite advanced if you want to start supporting things like decimal exponents and the like. What I will say is that you will definitely wan't to get used to using the Sub() command, the Number-to-String routine, as well as the Expr() command. There is no set way to do symbolic manipulation, but if you are up for the task, you have the tools you will be needing.

]]>` ``Input "TERMS?", C For(D,1,C Prompt A,B A->L1(D B->L2(D End For(D,1,C L1(D)L2(D->L1(D L2(D)-1->L2(D EDIT: Max({0,L2(D)-1->L2(D End Disp L1,L2`

obviously very rough… (and not tested, just typed this up right now)

]]>An example equation could be 3x

An actual program that does this would not be very helpful because its pretty simple math easily done in your head but my friend challenged me to make one anyway and i'm really not sure the best way to go about it. My current approach is to ask for the coefficients and exponents of each term but he wants to just enter the equation and have it give you the derivative. I'm really not sure how to do that other than with a string… in which case i would have no idea how to perform the operations on it.

Ideas?

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