If $f:\mathbb{R}^2 \rightarrow \mathbb{R}, f(x,y) = (y-x^2)(y-2x^2)$, then $(0,0)$ is a min. point of $f$ restricted to any line through origin.
39179
Why is $(0, 0)$ not a minimum of $f(x, y) = (y-3x^2)(y-x^2)$?
46622
Let $ Y = \{ (1,1),(0,0\} \subset \mathbb A_k^2$. Find the $ \mathbb I(Y)$.
22294
Maximum and minimum value of $\int_0^1 f(x)dx $ given $|f'(x)|<2$
114198
Showing that $y$ is irreducible in $\mathbb R[x,y]/(x^2+y^2-1)$.
95293
Proof that $|\sqrt{x}-\sqrt{y}| \leq \sqrt{|x-y|},\quad x,y \geq 0$
144745
Proof of: If $x_0\in \mathbb R^n$ is a point of local minimum of $f$, then $\nabla f(x_0) = 0$.
63590
Let $g$ be a function from $(0, 1)$ to $\mathbb{R}$ and $\int_0^1 g^2(x)dx$ finite. Does this imply that $\int_0^1 g(x)dx$ is finite?
144426
Example of a function $f:\mathbb{R}^2\to\mathbb{R}$ not differentiable at $(0,0)$, but has a directional derivative at $(0,0)$ in all directions
36099
Show that $\|f\|^{2}$ attains a minimum value on the interior of $B$
111290
If $f$ continuous and $\lim_{x\to-\infty }f(x)=\lim_{x\to\infty }f(x)=+\infty $ then $f$ takes its minimum.
1117
Is there a bijection between $(0,1)$ and $\mathbb{R}$ that preserves rationality?
64523
interior points and limit points of $\{(x,y): x^2+2y^2 < 1\}$
74673
True or false: if $f'(c)<0$, then $f$ is concave down at $x=c$?
112648
For every twice differentiable function $f : \bf R \rightarrow [–2, 2]$ with $(f(0))^2 + (f'(0))^2 = 85$, which of the following statements are TRUE?
34343
Determine all $f : \mathbb R \rightarrow \mathbb R$ such that $f(f(x) + y) = f(x^2 - y) + 4yf(x)$.
96382
Minimum of the Gamma Function $\Gamma (x)$ for $x>0$. How to find $x_{\min}$?
49240
$\forall x,y \in \mathbb{R}:\vert\cos x- \cos y\vert\leq\vert x-y\vert$