If I have the following $n \times n$ matrix   $$\begin{bmatrix}      2 &amp;      3 &amp; \cdots &amp;    n+1\\      3 &amp;      4 &amp; \cdots &amp;    n+2\\ \vdots &amp; \vdots &amp; \ddots &amp; \vdots\\ n+1    &amp; n+2    &amp; \cdots &amp;     2n\\ \end{bmatrix}$$  how can I determine its rank?  I know that I need to check for the maximum number of linearly independent columns. However, I’m having a hard time determining the linearly independent columns. Thanks for those who’ll help.
Let $A$ be a $n\times n$ matrix with entries $a_{ij}=i+j $ . Calculate rank of $A$.  My work : I noticed that A is symmetric . Hence all of its eigen vectors are real .. That is all i have got .   Your help will be highly appreciated .Thank you .
I know it existed as sort of a folder in Windows Explorer in at least Windows XP, but I just can't seem to find it in Windows 7...  How can I take a picture with my webcam in Windows 7 without using any 3rd party tools? List all my drafts In GMAIL you can list all your boss-tell-off and wife-cuss-out emails by clicking Drafts    I'd like to see my started-but-never-finished responses, possibly between x Answers and y Votes in /&lt;&lt;user&gt;&gt;/Stats/? OS X El Capitan installation error: AMD-Action:authenticate:SP When doing a clean re-installation of El Capitan (highest supported version) from a bootable USB on an older Mac (MBP, 15-inch, Late 2008), I get this error:  An unexpected error occured while signing in. AMD-Action:authenticate:SP  The error shows up, while logging in with the Apple ID into the App Store in the installer.  I tried with different Apple IDs,  Also tried running these commands in the Recovery Terminal and restarting: csrutil clear csrutil enable Is there a known well ordering of the reals? So, from what I understand, the axiom of choice is equivalent to the claim that every set can be . A set is well ordered by a relation, $R$ , if every subset has a least element. My question is: Has anyone constructed a well ordering on the reals?  First, I was going to ask this question about the rationals, but then I realised that if you pick your favourite bijection between rationals and the integers, this determines a well ordering on the rationals through the natural well order on $\mathbb{Z}$ . So it's not the denseness of the reals that makes it hard to well order them. So is it just the size of $\mathbb{R}$ that makes it difficult to find a well order for it? Why should that be?  To reiterate:   Is there a known well order on the Reals? 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Is there any instances of some form of emergency services that tractor beam chunks of debris to safe landing places or repulsor towers that can slow or suspend it until it can be taken apart safely? Even disintegration lasers or emergency force field generators like the types deployed on Hoth as they must have the energy output capable of sustaining it. This IS the galactic capital so must have some advanced tech at its deposal. Even now in our own development humans have certain preventative measures for all types of threats and ways of tracking them, plus responses or fall back plans. I think this is just something I've grown used to but can't remember any proof.  When differentiating and integrating with trigonometric functions, we require angles to be taken in radians. Why does it work then and only then? Is there a way to Inset in the opposite direction (not Outset)? Is there an operation similar to inset that creates faces in the opposite direction? That is, instead of creating faces inwards, they create faces outwards? A normal inset operation:  What I would like: What is average distance from center of square to some point? How to prove this for positive real numbers? $$a+b+c\leq\frac{a^3}{bc}+\frac{b^3}{ca}+\frac{c^3}{ab}$$  I tried AM-GM, CS inequality but all failed. Can you take Gorrilla Glue in Hold Luggage on a plane? Duality discrete math problem This is the only answer I got wrong on my HW and the prof does not want to give us the correct answers before our midterm     The dual of a compound proposition that contains only the logical operators $\lor$ , $\land$ , and   $\neg$ is the compound proposition obtained by replacing each $\lor$ by $\land$ , each $\land$ by $\lor$ , each $\def\T{{\rm T}}\def\F{{\rm F}}$   $\T$ by $\F$ , and each $\F$ by $\T$ . The dual of $s$ is denoted by $s^*$. 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