Showing a function is differentiable using the defition
91430
If $f$ is twice differentiable, $\big(f(y) - f(x)\big)/(y-x)$ is differentiable
115635
Differentiability of antiderivative and continuity of derivative
144323
Differentiation of a function
117906
Show that $\liminf\limits_{x\to \infty}|f'(x)|=0$ if $\lim\limits_{x\to \infty}f(x)/x=0$ and $f$ is differentiable
27360
How to differentiate formally?
68538
Show that if $ A(t) \in \mathbb{R ^{n×n}}$ is a differentiable function of $t$ then $\frac{d(det A(t))}{dt}$
122003
From the limit definition of differentiability, determine where the function $f(x) = \sqrt{x}$ is differentiable?
68973
Is the determinant differentiable?
53376
A continuous, nowhere differentiable but invertible function?
59279
Example of function that is differentiable, but the second derivative is not defined
97146
differentiate with respect to a function
94193
determine whether $f(x, y) = \frac{xy^3}{x^2 + y^4}$ is differentiable at $(0, 0)$.
38923
What can we say about differentiability of $f$ at $c$?
135199
Looking for a function $f$ that is $n$-differentiable, but $f^{(n)}$ is not continuous
38417
How to find the non-differentiable point(s) of a given continuous function?
31051
Is $f(x,y)=(xy)^{2/3}$ differentiable at $(0,0)$?
150447
Prove a differentiable function between banach spaces is continuous