Recursive Function with conditionals
Recursive function, if and which statements
In the cases of black holes that form from supernova and collapse of a massive star, I understand that in most of these cases, the star loses significant amounts of mass from the explosion. Presumably, after this point as the remaining mass becomes more dense as it further collapses unto itself, it eventually becomes a black hole with gravitational force greater than that of its parent star. But, if gravity is based on mass, how can the black hole have greater gravitational force than the star from which it is formed? Adding a class to “body” I'm trying to add a custom CSS class to the &lt;body&gt; tag, How can I modify or pre-process the &lt;body&gt; tag to add the class body, Is it right to style the &lt;body&gt; tag with css file? And now I am unable to chmod it back.. or use any of my other system programs. Luckily this is on a VM I've been toying with, but is there any way to resolve this? The system is Ubuntu Server 12.10.   I have attempted to restart into recovery mode, unfortunately now I am unable to boot into the system at all due to permissions not granting some programs after init-bottom availability to run- the system just hangs. This is what I see:  Begin: Running /scripts/init-bottom ... done [   37.062059] init: Failed to spawn friendly-recovery pre-start process: unable to execute: Permission denied [   37.084744]  init: Failed to spawn friendly-recovery post-stop process: unable to execute: Permission denied [   37.101333] init: plymouth main process (220) killed by ABRT signal   After this the computer hangs. I am just starting into calculus and I have a question about the following statement I encountered while learning about definite integrals:  $$\sum_{k=1}^n k^2 = \frac{n(n+1)(2n+1)}{6}$$  I really have no idea why this statement is true. Can someone please explain why this is true and if possible show how to arrive at one given the other? Does deleting iCloud photos affect them on devices? If I delete a photo from my iCloud will it also be removed from my devices that are connected to my account? What's wrong with this division? I think there's a lot for me to learn about data types. Why this happens  double result = ((3/8)*100).ToString();   it gives zero .. should be 37,5 ... :( How to add custom objects to the "add object" menu? Why "a user" instead of "an user"? I am getting confused while using an article an. Because an is used while referring to vowels (a,e,i,o,u).  But today I read an article where for user they used a user.  My question is, why was an not used?  Could someone explain this with an example? "Subject, verb, direct object, object complement" versus "subject, verb, indirect object, direct object" Reading English Grammar (HarperCollins College Outline, published by HarperResource, an imprint of HarperCollinsPublishers) I found a chapter (Sentence Basics) that explains that in English there are different sentence patterns; in particular   Subject, verb, direct object, object complement Subject, verb, indirect object, direct object   The chapter reports the following example for the patterns:     Alice called Charles Professor Miller.   Alice gave Charles the rabbit.   What is the difference between the two kind of sentences? What is the difference between the object complement in the first case, and the indirect object in the second case?  PS: The question, which could appear silly, comes from the fact in my first language there is only the object complement. Can't insert code in my beamer slide Change \textwidth after first page in scrlttr2 Show $\frac{1}{4}\leq \mu(A\cap B \cap C)$ Let $\{X,\mathcal{A},\mu\}$ be a probability space. Let $A$, $B$, $C$ be sets in $\mathcal{A}$, which satisfy $$\mu (A\cap B)\geq \frac{1}{2}, \quad \mu (A\cap C)\geq \frac{1}{2}, \quad \mu (B\cap C)\geq \frac{1}{2}.$$ Show that $\frac{1}{4}\leq \mu(A\cap B \cap C)$.  I've managed to show in a previous assignment that $$\mu(A\cap B \cap C)\leq \min\{\mu (A\cap B), \mu (A\cap C), \mu (B\cap C)\},$$ but now I'm stuck with the above inequality. I've tried to draw it, but still no luck. Any hints? What are the solutions to $z^4+1=0$? Background: One of my co-authors faced problem of compiling the paper that I had built using TexStudio and MikteX 2.9 on his Mac Machine running TexLive.   ShareLaTeX Role: So, one solution is to use ShareLaTeX. But the first problem pops in mind is how safe is uploading unpublished article to a publicly accessible portal?  What I did: I googled security and data breach of ShareLaTex and found nothing except some words from the ShareLaTex community about their word to ensure that our data are safe; perhaps this would not be enough.  My 1st Question: To what extent can I trust ShareLaTeX and put my ready-to-publish content there?   My 2nd Question: Is there any alternate way of sharing LaTeX with others around the globe without changing the underlying platform? Why does the dock appear on the left when my screen is locked? The dock doesn't work correctly after I enter my password, either. Dell Inspiron 3551 Unresponsive Touchpad I just got my laptop in the mail and I installed Ubuntu 14.04 LTS. It all went smooth until it booted up and I noticed my touch pad doesn’t work at all. It works perfectly on Windows and when I use a wireless mouse it works as well.  Here's my xinput:  ⎡ Virtual core pointer                          id=2    [master pointer  (3)]   ⎜   ↳ Virtual core XTEST pointer                    id=4    [slave  pointer  (2)]   ⎜   ↳ 2.4GHz RF  KEYBOARD  AND  MOUSE               id=11   [slave  pointer  (2)]   ⎜   ↳ DLL06AB:00 06CB:78F1                          id=13   [slave  pointer  (2)]   ⎜   ↳ SynPS/2 Synaptics TouchPad                    id=15   [slave  pointer  (2)]   ⎣ Virtual core keyboard                         id=3    [master keyboard (2)]       ↳ Virtual core XTEST keyboard                   id=5    [slave  keyboard (3)]       ↳ Power Button                                  id=6    [slave  keyboard (3)]       ↳ Video Bus                                     id=7    [slave  keyboard (3)]       ↳ Power Button                                  id=8    [slave  keyboard (3)]       ↳ Sleep Button                                  id=9    [slave  keyboard (3)]       ↳ 2.4GHz RF  KEYBOARD  AND  MOUSE               id=10   [slave  keyboard (3)]       ↳ Integrated_Webcam_HD                          id=12   [slave  keyboard (3)]       ↳ AT Translated Set 2 keyboard                  id=14   [slave  keyboard (3)]       ↳ Dell WMI hotkeys                              id=16   [slave  keyboard (3)]     I would love to have my track pad working and I've done some googling and browsing of this site and nothing I've tried has worked. Any input would be great. Let me know if there’s any other information that can help remedy this. I'm pretty new to Linux. Thank you very much.  Edit: I've updated the kernel to 3.19 and checked my Additional Drivers which had nothing for me. Neither of which worked. In Dark Souls 2 there is a 'Shrine of Winter' near Sinners Rise. When you approach the shrine it will not let you open the door and a message pops up that says      Seek Mightier Souls   What does this mean and how do you open this shrine? Why does US Robotics destroy Lanning's house? Shortly after the death of Dr. Lanning, Detective Spooner travels to the doctor's house to look for clues.  While he is searching the house a demolition bot (which had been programmed to demolish the house the next day) goes on a rampage and destroys the house with Detective Spooner in it.   The house is fully furnished and appears to be in good condition. Why would US Robotics want to destroy the house with everything in it? Why not sell the house and everything inside? If I am thinking about using one of the 'fancy' top level domains such as .me or .tv should I be worried about how Google treats such domains?  Or to put it another way, if all other things are equal (good content, links etc.), will Google regard a .tv or .me as equal to a traditional .com or co.uk site? How can particles be emitted from particles? In a scene with two particle system configured as boids and boids brain set to fight, one swarm attacks the other. I would like to emit child particles as lines (laser or something) to visualize some fighting action. I couldn't find a way to setup the line emitting particle system, either they are created from the plane or further cones will be added. Is there a way to do this as I saw on a  but I didn't get the trick? Blend file   At blendersushi  the author says:  PARTICLE INSTANCE MODIFIER &gt; PARTICLES With this stacking thing, we can now pretty much emit Particles from emitted Particles, &gt; if you know how to set it up. Not very obvious, but basically you Instance some meshes &gt; (using Instance Modifier) and then add Particle System to the object with Instance &gt; Modifier. Make sure you have &quot;Use Modifier Stack&quot; turned on.  But I can't get this to work.