Slightly off topic: Mathematica's Derivative function, instead of differentiating with respect to a variable, takes the derivative of a function with respect to the argument. In other words, Mathematica takes the derivative and then plugs in the variable ξ.
– JungHwan MinOct 08 '16 at 19:53
Derivativefunction, instead of differentiating with respect to a variable, takes the derivative of a function with respect to the argument. In other words, Mathematica takes the derivative and then plugs in the variableξ. – JungHwan Min Oct 08 '16 at 19:53