Show that $f(x)$ cannot be zero
Is the following statement provable?
Which render engine renders faster? Blender Internal or Cycles? I wonder which render engine is faster? I mean, you have 2 identical scenes and render it using BI and Cycles. Which image will be generated faster? What will be the time difference?  Do you know any site (please post a link) which shows the results of such comparison? CPU Die temperatures reaches 90° C, is that normal? How can I customize a system locale? How to concatenate multiple lines of output to one line? Cyclic Quadrilateral Problems form_state->setRedirect(to_a_new_node_page) from the submitForm function, route "does not exist" issue I created a custom module, It generate a custom Form in a page. When I submit my form, I create a new node. So, I am redirect to the form page but I would like be redirect to the new node page.  I add this line at the end of my submitForm function :   $form_state-&gt;setRedirect('node/'.$mynewnode-&gt;id());   But when I submit my form from the website, I get the empty-white-screen-of-the-death. My apache log :   ... Uncaught PHP Exception Symfony\\Component\\Routing\\Exception\\RouteNotFoundException: "Route "node/153" does not exist. ...   And then, when I go manually to the node/153 page, there isn't any problem. The page work well.   My question : where is my mistake ? How can I set the redirection after create the new node ? Is it possible from the submitForm function ? Should I use the datetime or timestamp data type in MySQL? Would you recommend using a  or a  field, and why (using MySQL)?   I'm working with PHP on the server side. When using data.stackexchange.com I fail to remember if as [post link] is the correct alias to get the url for the post. Luckily the site has an  link. Unfortunately it is now broken. Can this be fixed? Getting error using JMeter behind a proxy I am new to JMeter and trying to run a test from behind a corporate proxy. I read on the same from apache site and followed the same process so as to run the test. However, i am still  unable to record a test from behind the proxy.      This message always appears after pressing on 'Start' recording:     After that, I have changed apache port to 8000 as in below and made it different      This time after pressing on start was this message How to install and configure Wine? I am looking for a step by step instruction to guide me in the ways of installing, configuring and debugging many of the issues new users have when dealing with Wine in Ubuntu.  What is the recommended way of installing Wine, some of the key issues that it has and how to solve them?  If I have a specific problem with an App in Wine, how do I go about solving it? What are the recommended steps to ensure that I can fix a problem related to an app I wish to use? Let $S = \{ax + by: x,y \in \mathbb{Z}\}$  and let $e &gt; 0$ be the smallest element in $S$. Prove that $e \mid a$, and hence prove that $e = \gcd(a,b)$  I'm afraid I can't provide much of my initial working here because I'm at a loss of how to start.  I suppose that to show $e\mid a$ I would have to show that $eg = a$ for some $g \in \mathbb{Z}$. But I have no idea how I would do this. Im working in a site, And I need to present many fields to be filled and the page, so accoding to a selecction before, I have all the field but I have the Api Name, and the object name, but, With this api object field name, how can I get the label????  Example. I have "Student__c", I need to present "Student" to the user.  Thanks a lot for ur help!    Ok, thanks for ur answuers but I think I did not explain well this situation.   I have a list of string, where I have the information but in Api's name.  I present this fields in a table, so the user is filling the fields but with an inputText and not with an inputfield!.. So, in this moment, I dont know what is the label of each field.  My question basically, if by means of a query I could know the label of a field, if I know the api field name and the object name.. My question is if there is a way to consult this info!...  I know if I have the object is enough using an inputfield, But I cant do that. Neither set the label with HTML directly 'cause this is something dynamic.   Anyone knows how can I know, or consult, I guess by means of a query, how to get this label names??? Does Auto White-Balance Really Work? How? dpkg-divert: error: rename involves overwriting `/usr/lib/xorg/protocol.txt' with different file `/usr/lib/xorg/protocol-precise.txt', not allowed Could one fire a bullet with sufficient speed to leave the Earth? How does background blur (bokeh) relate to sensor size? This is a somewhat theoretical question.  Suppose I first take a photo of a subject using a full frame sensor DSLR, with a given lens (say 50mm prime lens at f/3.5).  Now suppose I exchange the camera for an APS-C sensor DSLR (with a 1.6× crop factor). I keep the same lens (same focal length, same aperture) and I step back a few meters in order to maintain the field of view (at least keep the same magnification of the subject). I now take a second photo.  Clearly depth of field will have increased between the two photos. But what about background blur (for example, trees at infinity)? Will I have the same amount of background blur, or will that have changed?  I have read somewhere that background blur depends on the physical aperture size. In this case the physical aperture (physical focal length divided by f/stop) stays the same. But should this number be taken in relation to the sensor size? In which case with the smaller APS-C sensor, the physical aperture will be relatively bigger, which would mean more background blur. This would be rather counter-intuitive as we usually consider it to be more difficult to get background blur on an APS-C camera.  Please give the reasoning behind the answer. I would answer the question myself using this  but I can't manage to get it to run on my computer. On several occasions, I was reading a question thinking "I know a guy that knows the answer to this" and that guy (or gal) also happens to be a registered user. How can I bring this to the attention of this user? How can I check the SMART status of a SSD or HDD on current versions of Ubuntu 14.04 through 20.04? Windows 10 high memory usage (unknown reason) Travelling from London, Heathrow to Lusaka, via Jo'burg, how much time should we allow for the international connection in Jo'burg?  Is it a matter of arriving at one gate and leaving at another, or do you have to go through passport control, customs, security?