Why do similar matrices represent the same linear transformation?
Similar Matrices and Linear Transformations
How to Store Fresh Herbs What is the best way to store fresh herbs like parsley or cilantro?  I find I have about the same luck with them whether they are left in a plastic bag or I put them in a cup of water. Where can I download Ubuntu 16.04? I am unable to find the link for downloading Ubuntu 16.04 onto my   desktop/laptop. I am able to see the link only for 18.04, but I need 16.04. Install java Runtime Environment Have iPhone 4 with iOS 5.1.1 Trying to update to 6.1.2 (not the latest) via downloaded IPSW but unfortunately getting error:     iphone could not be restored device isn't eligible for the requested   build   After searching for fix all over the internet found some suggestion like putting # in hosts file in line gs.apple.com but not helped.  Have you any idea why I'm getting this error and can't restore iphone? Create a box using the tcolorbox package or any other? (image) I would like to make a box like the figure below. Can you assist me with text code using tcolorbox?   Thanks How to show the parent and child taxonomy term? Two icons on Unity Launcher on non-standard application launch I have an application which doesn't come from any Ubuntu repo (neither official, nor PPA) but available as tgz and supposed to be unpacked and ready to use. To be precise it is .   The problem is the  application when launched shows its own icon in Unity Launcher. After making a custom .desktop file and placing shortcut onto Unity Launcher (by dragging from the dash) and launching it I see two icons - one placed by me and another one with real application.  This is the .desktop contents:  [Desktop Entry] Version=1.0 Type=Application Terminal=false Exec=/opt/LightTable/LightTable Name=Light Table Icon=/opt/LightTable/core/img/lticon.png   One more thing. The /opt/LightTable/LightTable is bash script file and eventually /opt/LightTable/ltbin is being launched. I think this is the problem but have no idea how to fix the problem. How to redirect output to screen as well as a file? My aim is to log all output from a script into a directory that the script is going to create.  For example, I have:  ~/.abc.sh:  #! /bin/bash rails new myapp   When I run...  cd ~/code . ~/.abc.sh   ...that will create a new Rails app in directory ~/code/myapp.  When Rails is creating an app, it outputs a whole lot of text that I want to capture and store in a log file in the same directory the rails command newly created. I also want to display that text in the terminal as well.  How do I go about doing this? Prove that there is no retraction (i.e. continuous function constant on the codomain) $r: M \rightarrow S^1 = \partial M$ where $M$ is the Möbius strip.  I've tried to find a contradiction using $r_*$ homomorphism between the fundamental groups, but they are both $\mathbb{Z}$ and nothing seems to go wrong... It may be something that will happen to the person who is having the feeling but it may also be to several persons, as might occur with a highly destructive earthquake, for instance.   The word or phrase would be used in the following sentence:      “I’m no spiritualist but I have a feeling of ___. I hope it’s just a feeling."   EDIT - The phrase I'm looking for conveys a much stronger feeling than "I have a bad hunch". It is about something catastrophic which the person feels is "going to happen in a few minutes". Unable to mount Windows (NTFS) filesystem due to hibernation Whenever I boot Ubuntu, I get a message that it cannot mount my windows partition, and I can choose to either wait, skip or manually mount.  When I try to enter my Windows partition through Nautilus I get a message saying that this partition is hibernated and that I need to enter the file system and properly close it, something I have done with no problem so I don't know why this happens.    Here's my partition table, if any more data is needed please let me know.     Device Boot      Start         End      Blocks   Id  System /dev/sda1            2048    20000767     9999360   83  Linux /dev/sda2        20002814   478001151   228999169    5  Extended /dev/sda3   *   478001152   622532607    72265728    7  HPFS/NTFS/exFAT /dev/sda4       622532608   625141759     1304576   82  Linux swap / Solaris /dev/sda5        20002816   478001151   228999168   83  Linux How to draw a side line in table Every time I try to do something seemingly-simple in CSS, it doesn't work.  I have a content div that contains a 460x160 image. All I want to do is position the image at the bottom-right corner and wrap my text around it.  &lt;div id="contents"&gt;     &lt;img src="..." /&gt;     text text text text text text ... &lt;/div&gt;   So I want it to look like:  ------------------ | text text text | | text text text | | text text -----| | text text |    | ------------------   Doing it with a top-left or top-right image is cake:  #contents img { float:right; }  ------------------ | text text |    | | text text -----| | text text text | | text text text | ------------------   Now how do I push that to the bottom? The best I've come up with so far are:  #contents img { float:right; margin-top: 90%} // really needs to be 100%-160px  ------------------ | text text      | | text text      | | text text -----| | text text |    | ------------------   In this case the text does not print in the margin, so there is white space above the image.  #contents { position:relative; } #contents img { position:absolute; right:0; bottom:0; }  -or-  // move the img tag under the text in the html and: #contents img { float:right; margin-top:-160; }  ------------------ | text text text | | text text text | | text text -----| | text text | te | ------------------   In this case the text prints over or under the image.  So... how can I accomplish this? How to install tzdata on a ubuntu docker image? I have the following line in the Dockerfile.  RUN apt-get install -y tzdata   When I run it, it asks for my input. After I provided my input, it hung there. Does anybody know how to solve this problem?  Step 25/25 : RUN apt-get install -y tzdata  ---&gt; Running in ee47a1beff84 Reading package lists... Building dependency tree... Reading state information... The following NEW packages will be installed:   tzdata 0 upgraded, 1 newly installed, 0 to remove and 0 not upgraded. Need to get 189 kB of archives. After this operation, 3104 kB of additional disk space will be used. Get:1 http://archive.ubuntu.com/ubuntu bionic-updates/main amd64 tzdata all 2018i-0ubuntu0.18.04 [189 kB] debconf: unable to initialize frontend: Dialog debconf: (TERM is not set, so the dialog frontend is not usable.) debconf: falling back to frontend: Readline debconf: unable to initialize frontend: Readline debconf: (This frontend requires a controlling tty.) debconf: falling back to frontend: Teletype dpkg-preconfigure: unable to re-open stdin:  Fetched 189 kB in 1s (219 kB/s) Selecting previously unselected package tzdata. (Reading database ... 25194 files and directories currently installed.) Preparing to unpack .../tzdata_2018i-0ubuntu0.18.04_all.deb ... Unpacking tzdata (2018i-0ubuntu0.18.04) ... Setting up tzdata (2018i-0ubuntu0.18.04) ... debconf: unable to initialize frontend: Dialog debconf: (TERM is not set, so the dialog frontend is not usable.) debconf: falling back to frontend: Readline Configuring tzdata ------------------  Please select the geographic area in which you live. Subsequent configuration questions will narrow this down by presenting a list of cities, representing the time zones in which they are located.    1. Africa      4. Australia  7. Atlantic  10. Pacific  13. Etc   2. America     5. Arctic     8. Europe    11. SystemV   3. Antarctica  6. Asia       9. Indian    12. US Geographic area: `` The currently proposed Gravitational wave detection apparatus consists of Michelson Interferometer which is supposed to measure distances of the order of $10^{-22}$m. But the wavelength of the light used is in the order of micrometers ($10^{-6}$m). How is this possible? The conventional way to measure distance is by counting the interference fringes. But for path difference smaller than wavelength of laser light this is not possible. How do I connect to a MySQL database using a python program? Why doesn't an Environment texture appear when the world has a Volume Scatter shader? I'm working on lighting a scene in which I need to have both an Environment texture for the background and Volume Scatter for light cones, but when I check the volume section in World setting and choose the Volume Scatter, the environment becomes black background (but the lighting works as I want).  I'm using Blender 2.72  How can this be fixed? How to transfer a DVD to my hard drive Let $A\in M_{n\times n}(\Bbb R)$ so that $I\notin span(A,A^2,...,A^n)$. Prove that $\det(A)=0$. Let $A\in M_{n\times n}(\Bbb R)$ so that $I\notin span(A,A^2,...,A^n)$. Prove that $\det(A)=0$.   I was thinking of showing $A$ is not invertible, meaning it has an eigenvalue of $0$. Since no matter the power you give to $A$, it is still not the identity, you can deduce that at least one eigenvalue is indeed $0$. However this doesn't work if you have different eigenvalues in the Matrix, so I got stuck.  Help will be most appreciated. What is this Disney scifi movie from the late 80s/early 90s?