Number format with currency symbol
How do I format a number to a dollar amount in PHP
How do I specify unique constraint for multiple columns in MySQL? Find the general solution of $y'= a^{x + y}$ where y is the function How should I approach this problem? Should I put ln logarithm on both sides and move factor of variable of lnx on right side in front of the ln, or do somehing else? I understand general solving and types of solving these differential equations of first order, but I have no idea what my next step should be. Evaluating $\int_{-\infty}^{\infty}\frac{1}{(x^2+b^2)^2}dx$ Find $$\int_{-\infty}^{\infty}\frac{1}{(x^2+b^2)^2}dx$$   We see that the only poles are at $x=\pm bi$.  Integrating over the semicircular contour implies that it is equal to $2\pi i*Res_{(+bi)}$ because the integral over the circular arc is $0$.  So now I just need to calculate the residue at $+bi$. Can anyone give hints on how to do this?  I was thinking about multiplying by $(x-bi)^2$ and then evaluating at $bi$ but I'm not sure why this even makes sense. If photons have no mass, how can they have momentum? As an explanation of why a large gravitational field (such as a black hole) can bend light, I have heard that light has momentum. This is given as a solution to the problem of only massive objects being affected by gravity. However, momentum is the product of mass and velocity, so, by this definition, massless photons cannot have momentum.  How can photons have momentum?   How is this momentum defined (equations)? Force LaTeX image to appear in the section in which it's declared Possible Duplicates:           How can I force an image in a LaTeX documents to appear in the section in which I declared it?  I don't want that an image about "Section A" to appear in "Section F". :(  I actually include an image with  \begin{figure}[ht] \begin{center} \includegraphics[scale=0.7]{./img/RobotManipulator3D_WorkSpace.png} \end{center} \caption{3D View of the robotic workspace (in red).} \label{Img:3DRobotWorkspace} \end{figure} Keep items in inventory on death in Minecraft How to validate an email address using a regular expression? Where can I buy an Ubuntu Phone? I need to buy an Ubuntu phone, where can I buy it? It is unavailable everywhere. Reducing size of KML file (after converting from Shapefile) How to rename objects with python? I want to rename the number 1->picture (32) with python not the number 2->picture with the (3745), can someone help me with that ? I was naively validating my binomial logit models by testing on a test dataset. I had randomly divided the available data (~2000 rows) into training (~1500) and validation (~500) datasets.   I now read a post in another thread ( Frank Harrell) that causes me to question my approach:     Data splitting is not very reliable unless you have more than 15,000   observations. In other words, if you split the data again, accuracy   indexes will vary too much from what you obtained with the first   split.   How serious is this worry and what are ways around it? The OP speaks of "resampling" but not sure how that works here for validation.   Edit: Adding context as per @Bernhard's comment below: Can I completely disable Cortana on Windows 10? Displaying multiple fields as labels if one field is null in QGIS? I am having some issues trying to show multiple fields for a single label in QGIS. In QGIS2.6, attempting to display labels for a feature consisting of multiple fields results in an empty label if one of the fields is null. So for example, in the label expression dialog:  concat("Temp Site",'\n',"Notes",'\n',"Function")   will function normally unless one of the fields is null, then it results in no label being shown. Using the '||' operator instead in the expression dialog also results in the same behaviour:  "Temp Site" || '\n'  ||  "Notes" || '\n'  ||  "Function"   Is there a way to display the labels even if one of the fields is null? 3 more votes from other users are needed to close this question.   This is the message I got hovering the mouse over close voting tab.   I wonder can we begin any sentence with a numeric value? Is it good practice? Have men and women in the Wizarding World always had relatively equal rights? There are racial struggles and examples of racism, (Muggle-borns, centaurs, hous-elves, goblins, etc.) but are there any examples in the Wizarding World of sexism?  Have witches and wizards always had equal rights? How can I install Skype on 32-bit Ubuntu 14.04? How to replace spaces with newlines/enter in a text-file? I have simple text file named "example".  Reading with terminal command: cat example  Output:  abc cdef ghi jk lmnopq rst uv wxyz   I want to convert (transform) into following form: (expected output from cat example)  abc cdef ghi jk lmnopq rst uv wxyz   How can I do this via the command-line?   (This is only an example file, I want to convert word's position in vertical-column) A situation came up in my session where a fighter used his Shield Master Shove feature to shove a Giant Crocodile that was currently restraining another PC using it's bite+grapple ability.  I did a quick check at the time and did not find anything related to shove, although in the  condition description it states:     The condition also ends if an effect removes the grappled creature from the reach of the grappler or grappling effect, such as when a creature is hurled away by the thunderwave spell.   I ruled at the time that a shove would count in a similar way to being "hurled away" however I wasn't sure and said I would find more concrete information for the future.  I have searched high and low for somebody else asking this specific question but have yet to find it. I saw some reference to a Jeremy Crawford tweet about involuntary movement and grappling however I am unable to find it.  If a third party "shoves" a creature that is grappling another, does it only shove the grappler away, or does it move both the grappler and grappled?  I drew a diagram:   (; this question relates to if a third party shoves the grappler instead, so it's not a duplicate.) Is there exist a function defined on the real or complex numbers that, restricted to the integers, is equal to the factorial? Evaluating indefinite integrals of the form $\int \frac{x^2 \,dx}{a x^5 + b}$ Evaluate the indefinite integral   $$\int \frac{x^2 \,dx}{a x^5 + b},$$   for real parameters $a, b \neq 0$.   No apparent substitutions simplify the expression (if the exponent of $x$ were an integral multiple of $3$, this would suggest the substitution $u = x^3$, $du = 3 x^2 \,dx$, but the exponent is not). Applying integration by parts with $u = a x^5 + b$, $dv = x^2 dx$ is straightforward, but it produces an integrand with a much larger degree in the denominator and so appears only to make the situation worse. Applying integration by parts instead with $dw = \frac{x^k dx}{a x^5 + b}$ results in integrating $\frac{x^k dx}{a x^5 + b}$, which except when $k \equiv 4 \pmod 5$ (which doesn't appear immediately fruitful), doesn't appear much easier than the given integral.