New posts in Derivatives

Is the derivative always nonnegative in a neighbourhood of a minimum?

What is the derivative of $\log \det X$ when $X$ is symmetric?

Is a continuous function with zero “Taylor approximation” smooth?

Why can a linear "ordinary" differential equation have non-linear coefficients of independent variable?

Give an example, with proof, of a function differentiable at a point, whose derivative is non-differentiable that point.

Unfriendly function to study

Gradient of $A \mapsto \sigma_i (A)$

Can the derivative of a real function be imaginary?

Does $f'(x)>\frac{f(x)}{x}$ for $x>0$ imply $f$ is convex?

Find maximum value of $\int_{1}^3\frac{f(x)}{x}dx$ if $\int_{1}^{3}f(x)dx=0$ and also $-1\leq f(x)\leq 1$