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xavierm02's user avatar
xavierm02
  • Member for 13 years
  • Last seen more than a week ago
19 votes

Prove $|e^{i\theta} -1| \leq |\theta|$

18 votes
Accepted

What does the notation $f\colon A\to B$ mean?

16 votes

Compute the $n$-th power of triangular $3\times3$ matrix

15 votes
Accepted

Prove projection is self adjoint if and only if kernel and image are orthogonal complements

14 votes

difference between normed linear space and inner product space

12 votes

$f: \mathbb{R} \to \mathbb{R}$ satisfies $(x-2)f(x)-(x+1)f(x-1) = 3$. Evaluate $f(2013)$, given that $f(2)=5$

11 votes

Symbol for the set of odd naturals?

11 votes

Right and left inverse

10 votes
Accepted

Prove: If $\lim_{n\rightarrow\infty}|a_n| = 0$, then $\lim_{n\rightarrow\infty}a_n = 0$

10 votes
Accepted

Prove that if a is a root of $f(x)$ then $\overline{a}$ is also a root

10 votes
Accepted

Let $z \in \mathbb C$, $|z| = 1$. Assume the sequence $a_n = z^n$ is convergent. Prove $z = 1$.

10 votes
Accepted

What is the total number of distinct sums possible from tossing six, six-sided dice?

10 votes

How to find the determinant of this $3 \times 3$ Hankel matrix?

9 votes
Accepted

CFG for language

8 votes
Accepted

Proving that $ f(1)=\frac{1-\sqrt{5}}{2}$ for this function

8 votes
Accepted

Derivative of a map involving the matrix inverse

7 votes

How to compute the Lipschitz constant for the multivariate function $f(x,y)=1-xy$?

7 votes

why geometric multiplicity is bounded by algebraic multiplicity?

7 votes
Accepted

Prove that a square matrix commutes with its inverse

6 votes

Does $\det(A + B) = \det(A) + \det(B)$ hold?

6 votes
Accepted

Showing that if $\lim_{x\to\infty}xf(x)=l,$ then $\lim_{x\to\infty}f(x)=0.$

6 votes
Accepted

No isomorphism between $(\mathbb R,+)$ and $(\mathbb R^*, \times)$

5 votes
Accepted

Prove or disprove: $ A^2 = I \Longrightarrow A=I \vee A=-I $

5 votes

Function Notation

5 votes
Accepted

About $2\times 2$ similar matrices...

5 votes
Accepted

How to solve this formula?

5 votes

An abelian group is not isomorphic to an non-abelian group.

4 votes

Bijection between Prime numbers and Natural numbers

4 votes

Is the series $\sum\limits^{\infty}_{n=0} x^{n}\cos(n\theta)$ absolutely convergent for $|x|<1$?

4 votes

Fibonacci and the algebraic expression $x^2-x-1$

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