Accepting symbolic derivatives as answers.
-
I'd like to ask students chain rule questions with unspecified functions, such as "evaluate the derivative of sin((h(x))^2)" and have Mobius accept a form of the answer containing, say, h'(x).
Which question type should I use? How should the answer algorithm be coded? I haven't been able to find any information about symbolic derivatives in the documentation.
-
I think I can answer my own question. I've managed to get this to work using the maple-graded question type, formula answer, symbolic entry only (so that prime notation can be used). The key seems to be that the maple-generated answer contain the operator D rather than the command diff. For example, if you ask maple to differentiate sin(f(t)), maple will respond with cos(f(t))*diff(f(t),t). But if you ask maple to differentiate sin(f(c*t)), then it responds with cos(f(c*t))*D(f)(c*t)*c. You just need to substitute c=1 into the result.
The following algorithm works for a question like "find the derivative of sin(f(t)), assuming f is differentiable":
$g=maple("sin(f(c*t))");
$ans=maple("subs(c=1,diff($g,t))");
This will enable students to enter their answer symbolically using f'(t).