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Skrrrrrtttt
  • Member for 6 years, 8 months
  • Last seen more than 2 years ago
4 votes
2 answers
360 views

Prove $|z^{5}+135| \geq 108$ Complex Numbers

3 votes
3 answers
3k views

Proving that $f(x+y) = f(x) + f(y)$ and $f$ being continuous at one point implies that $f$ is continuous on ${\bf R}$ [duplicate]

3 votes
2 answers
366 views

prove that there is no k such that $x^2-x+k$ divides $x^{135}+x+2016$

3 votes
1 answer
105 views

Prove that $perp_\vec{n}(\vec{x})=\frac{\vec{x}\cdot\vec{a}}{||\vec{a}||^2}\vec{a}+\frac{\vec{x}\cdot\vec{b}}{||\vec{b}||^2}\vec{b}$

2 votes
1 answer
347 views

Taylor Remainder, $\arcsin(x)$

2 votes
2 answers
1k views

Proving piecewise function is not Riemann integrable

2 votes
3 answers
197 views

Calculate remainder when $2^{403}$ is divided by 22

2 votes
1 answer
355 views

Newtons Cooling Law estimate constant

2 votes
3 answers
239 views

express $\sum_{n=1}^{135} (1-i)^n$ in standard form, Complex numbers

2 votes
2 answers
122 views

Find all eigenvalues for $L(\vec{x})=\vec{x}-2proj_\vec{n}(\vec{x})$ for some non-zero vector $\vec{n}$

2 votes
5 answers
738 views

Taylor series for $\ln(x+4)$ about $x=-1$

2 votes
3 answers
59 views

Proving that if $L(\vec{v}_1),\ldots,L(\vec{v}_k)$ spans $W$ that $\dim(V) \geq \dim(W)$

2 votes
1 answer
133 views

prove that every eigenvalue $\lambda$ of $A$ must satisfy $\lambda=-i\bar \lambda$

2 votes
2 answers
79 views

$f$ is differentiable and satisfies $f(t\vec{x})=t^pf(\vec{x})$ prove $\vec{x} \cdot \nabla f(\vec{x}) = pf(\vec{x})$

2 votes
1 answer
2k views

prove that $x^4+y^4-4b^2xy \geq -2b^4$ for all $x,y \in \Bbb{R}$?

1 vote
3 answers
128 views

volume of surface given by $(x^2+y^2+z^2)^2=x$

1 vote
1 answer
559 views

Proving certificate of optimality

1 vote
1 answer
285 views

Strong Duality: If Dual is optimal then primal is optimal

1 vote
2 answers
1k views

Cauchy-Euler equation change of variables

1 vote
1 answer
327 views

Exponential Distribution: Expected Value waiting in line

1 vote
1 answer
100 views

$A$ is an $n \times n$ diagonalizable matrix with exactly $k$ non-zero eigenvalues, find a basis for $Range(L)$

1 vote
4 answers
303 views

suppose $\sum a_n$ converges. Is it true that then $\sum (-1)^na_n$ will

1 vote
2 answers
349 views

Find all pairs of complex numbers (x,y) satisfying $xy=-1$ and $x^3-y^3=-1$

1 vote
4 answers
2k views

$\cosh(x)$ and $\sinh(x)$ satisfying second order differential equation

1 vote
4 answers
901 views

prove that 15 divides $n^7+2n^5+4n^3+8n$ for any integer n

1 vote
6 answers
2k views

Sum of positive divisors if and only if perfect square

1 vote
2 answers
487 views

$ax+by=d$ has integer solutions then $ax+by+cz=d$ has integer solutions

1 vote
4 answers
919 views

Proving integral diverges limits

0 votes
1 answer
59 views

Proving that a basis exists for a vector Subspace

0 votes
3 answers
58 views

Proving vectors are orthogonal