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I type in my equations using ctrl+- to make it look nice and my answer outputs in "Subscript^(0,1)[a,b]" form? What is going on? In the answer some bits are displayed with the actual subscripts and some are displayed in the above form, even for the same variable.
Edit: more specifics I am taking the partial derivative of a function H wrt to b. H is a function of many variables one of which is a_b. Is it possible that Mathematica is trying to take the derivative of the subscript because there is a b in there?
H=d k2 + c^2 k4 + k5 s^2 + k1 U + k3 \[Theta] + (g (1 - d - U - \[Theta]) \[Theta] - U (1 + s Subscript[e, s])) Subscript[\[Lambda], 1] + (-c d + s U Subscript[e, s]) Subscript[\[Lambda], 2] + U Subscript[\[Lambda], 3]
DHds = Simplify[D[H, s]]