Let $f(x,y) = (y-x^{2})(y-2x^{2})$. Show that on any straight line through $(0,0)$ $f$ has a minimum
131536
Maximum and minimum restricted
48275
$f$ defined $|f(x) - f(y)| \leq |x - y|^{1+ \alpha}$ Prove that $f$ is a constant.
31295
$x+y\sqrt{2}$ infimum ($x,y\in \mathbb{Z}$)
109896
Proving that the function $f(x,y)=\frac{x^2y}{x^2 + y^2}$ with $f(0,0)=0$ is continuous at $(0,0)$.
114844
Global maxima/minima of $f(x,y,z) = x+y+z$ in $A$
22294
Maximum and minimum value of $\int_0^1 f(x)dx $ given $|f'(x)|<2$
57736
Minimum value of $\left(a+\frac{1}{b}\right)^2+\left(b+\frac{1}{c}\right)^2+\left(c+\frac{1}{a}\right)^2$
72813
If $X$ and $Y$ are uniformly distributed on $(0,1)$, what is the distribution of $\max(X,Y)/\min(X,Y)$?
116851
Show that f(x) is convex
33389
What's the minimum of $\int_0^1 f(x)^2 \: dx$, subject to $\int_0^1 f(x) \: dx = 0, \int_0^1 x f(x) \: dx = 1$?
109601
Does the equation $\displaystyle min_{x,y} f(x,y)=min_{y}min_{x}f(x,y)=min_{x}min_{y}f(x,y)$ always hold for a minimization problem?
11744
Maximum and minimum of $f(x)=\cos(\sin(x))-\sin(\cos(x))$
125707
A simple proof (hopefully) for $2^x \neq 0$
76148
Show that $\exists c \in \mathbb{R} : f(c) = 0$
149764
If $f$ s twice differentiable and satisfies the following constraints, prove $f'(0)>-\sqrt 2$
139436
Show function $f(x,y)=(x^2-y^2,2xy)$ is $1$-$1$ by Inverse Function Theorem
76863
How to show $ \sup \inf g(x,y) \leq \inf \sup g(x,y)$?