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15h
asked Always “one double root” between “no root” and “at least one root” ? (Second version)
16h
answered Surprising necessary condition for a “shift-invariant” determinant
16h
asked Always a double root between “no roots” and “at least one root”?
1d
answered A Sperner type problem on infinite antichains
Jul
24
answered Prove that: $\sum \frac{a^2+2bc}{(b+c)^2}\geq \sum \frac{3}{2}\frac{a}{b+c}$
Jul
20
asked Discrete Cauchy integral formula : The interior values are always convex combinations of exterior values for harmonic functions?
Jul
18
answered Help with complicated functional equation
Jul
17
answered prove $(a+b+c)^n=a^n+b^n+c^n$ if $(a+b+c)^3=a^3+b^3+c^3$
Jul
16
answered How find this P(x) if $ (x^3 - mx^2 +1 ) P(x+1) + (x^3+mx^2+1) P(x-1) =2(x^3 - mx +1 ) P(x) $
Jul
13
answered Decomposing a matrix representation
Jul
12
answered Minimum of $|\det(X+iC)|$
Jul
11
answered Optimize $x^2 + y^2 +2z^2 +z(x^2-y^2)$ subject to $x+y=2$
Jul
3
answered How to prove the sequence $\{b_n\}$ with $0 \leq b_{n+1} \leq b_n + a_n$ converges, where $a_n \geq 0$ converges to $0$.
Jul
1
answered Real numbers that are not the roots of any polynomial equation with algebraic coefficients
Jul
1
asked Is there a probabilistic proof of the inequality $4p(1-p) \leq 1$ for a probability $p$?
Jun
23
answered being polynomial is a local property
Jun
21
answered Let $K_1(0) := \{x \in \mathbb{R}^2: \|x\|_2 < 1\}$ and $S := K_1(0) \setminus \mathbb{Q}^2$. Is M path connected?
Jun
14
asked Is there a simpler/better proof of this simple trigonometric property?
Jun
13
asked Is there a simple procedure to produce algebraic numbers of modulus one that are not roots of unity?
Jun
12
asked Does this polynomial have all its roots both distinct and real?