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Fundamental Theorem of Calculus for definite integrals... assume continuity?


So here's the problem:


I can evaluate the indefinite integral:


Integrate[D[u[x], x], x]


u[x]


However, I'd like to evaluate:


Integrate[D[u[x],x], {x, x0, x1}]

and get



u[x1] - u[x0]

Or especially, evaluate


Integrate[D[u[x, y], x], {x, x0, x1}]


and get



u[x1, y] - u[x0, y]

Is there a way that I can assume that D[u[x], x] is continuous in the range x0 to x1? Is there a some assumption that can be met in order for me to evaluate the fundamental theorem of calculus?




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