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    Counting Question Concerning Circular Arrangements

    Homework Statement I have two questions. I'm not sure if I'm allowed to post two at once so I'll start with one "Twenty boys and twenty girls are to take a ride on a Ferris wheel with twenty pods. How many ways can they be arranged if each pod is to contain one boy and boy girl" Homework...
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    Graph Theory: Finding the number of vertices

    Homework Statement 1. How many vertices will the following graphs have if they contain: (a) 12 edges and all vertices of degree 3. (b) 21 edges, three vertices of degree 4, and the other vertices of degree 3. (c) 24 edges and all vertices of the same degree. Homework Equations "Theorem 1 In...
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    Euler's Approximation

    Homework Statement y'+y=3+x y(0)=1 (a) Find approximate values of the solution of the given initial value problem at t = 0.1, 0.2, 0.3, and 0.4 using the Euler method with h = 0.1. Homework Equations yn+1 = yn + f(x0, y0)(x-x0). Adjusting 0 for the next number as we go up The Attempt at a...
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    Identities sin, cos, tan etc. stuff

    Homework Statement ((cos x)/(1+sin x))+((1+sin x)/(cos x)) Homework Equations The Attempt at a Solution multiplied the left equation by (cos x)/(cos x) and the right fraction by (1+sin x)/(1+sin x) get ((cosx)^2 +(1+sinx)^2) / (1+sinx) (cos x) and I have no idea where to go from here
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    Optimization (I believe it's called) word problems

    Homework Statement A real estate company owns 180 apartments, which are fully occupied when the rent is $300. The company estimates that for each $10 increase in rent, 5 apartments will become unoccupied. What rent should be charged so that the company will receive the max income? Homework...
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    Practicing for SAT Math and had my first four part miserable failure sequence

    For these four practice problems, I had little idea what the hell to do (plugging in seemed worthless), could anyone help? Sorry if this isn't what the board is suppose to be used for. Answers in spoiler tags. If k and h are constants and x2+kx+7 is equivalent to (x+1)(x+h), what is the value...
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    Java Pictures not showing up (Java)

    The error: "Exception in thread "main" java.lang.NullPointerException at javax.swing.ImageIcon.<init>( at Buttons.<init>( at Buttons.main( Java Result: 1" The code: _______________________________________ import...
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    Math.PI comes up with cannot find symbol error

    Math.PI comes up with "cannot find symbol" error class Pi { public static void main (String[] args) { float radius=Float.parseFloat(args[0]); float shortPi=(float) Math.PI; float circ= shortPi *(radius+radius); float area= shortPi *(radius*radius); System.out.print("with Pi...
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    Java Help with arguments in Java

    I'm suppose to type this in and get a certain error and I did: So the writer says I need to type in three arguments, and his sense of humor brings me to do this: I click OK Then when I click Run again I again get...
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    Java Can someone help me with Java installation on windows 7

    I bought a book for beginners and it said "On Windows Vista or Window XP, navigate through Start, Control Panel, System, Advanced (System Settings), Environment Variables. Select the System Variable named "Path" and then click the Edit button. Add the address of Java;'s bin sub directory at the...
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    I'm trying the super basics and the command prompt keeps disappearing

    For the second part of the tutorial, I'm suppose to compile and run to see what the output is. But, each time I click compile and run the command prompt shows up for less than a second and then goes away. What am I suppose to do?