map is differentiable if all compositions with smooth maps are smooth
53809
Continuous map of differentiable manifolds is differentiable if differentiable functions pull back to differentiable functions
18734
Showing that a function is differentiable
158344
Uniform continuous maps that converge uniformly to a function f. What can we say about f?
61122
A continuous mapping is determined by its values on a dense set
65953
Cardinality of the set of differentiable functions
120784
Differentiablility over closed intervals
103924
Kernel of a substitution map
138784
Is the differentiation operator an open mapping?
71487
Real Analysis: Continuity of a Composition Function
56936
$\frac{\partial f_i}{x_j}=\frac{\partial f_j}{x_i}\implies(f_1,\ldots,f_n)$ is a gradient
97382
Continuous differentiability implies Lipschitz continuity
143564
Uniform convergence of derivatives, Tao 14.2.7.
111470
Proof of differentiability of $f(x)$
58988
Composition of convex function and affine function
107148
Does there always exist a continuous/smooth map from $\mathbb{R}^n$ onto a manifold $M^n$?
24126
When functions commute under composition
77624
Characterization of sets of differentiability