Smooth function not analytic at any $ x$
101281
Does there exist a smooth function which is nowhere analytic?
123981
Is it possible to write any bounded continuous function as a uniform limit of smooth functions
103241
A function that is continuous at the origin but not differentiable there
83915
Showing that a function is not differentiable
86284
A typical $L^p$ function does not have a well-defined trace on the boundary
128862
Prove no existing a smooth function satisfying ... related to Morse Theory
18611
An analytic function with a simple pole
127538
Show $f(x)=x\ln x$ is not uniformly continuous
116659
Manifold that is NOT smooth
85092
Proving $ f(x) = x^2 $ is not uniformly continuous on the real line
87743
Is a function whose derivative vanishes at rationals constant?
5295
Can the graph of a bounded function ever have an unbounded derivative?
7945
Approximate $|x|$ with a smooth function
117338
Counterexample to second derivative test when f''(x) is not continuously differentiable
123602
Non integer derivative of $1/p(x)$
41847
Uniformly continuous function with unbounded variation
49604
Can a function "grow too fast" to be real analytic?