MuPAD® provides two functions for differentiation. The choice of the function depends on which type of object you want to differentiate. To differentiate mathematical expressions, use the diff command. For example:
diff(cos(x), x); diff(x^3, x)
To differentiate a function or functional expression, use D or its shortcut '. Using this command, you can differentiate any standard mathematical function or your custom created function. For example:
D(cos); f := x -> x*sin(x): f'