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Thread: SUPER SIMPLE QUESTION!!!

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    Default SUPER SIMPLE QUESTION!!!

    I just started me java class and im confused about how powers work, such as

    Volume of Cylinder = PIE (radius)2(SUPPOSED TO BE SQUARE, NOT 2) *height


    how does the above translate to java code? specificly the power of 2, sry im stupid, thx


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    Default Re: SUPER SIMPLE QUESTION!!!

    For exponents you use:
    Math.pow(A, B); //A is the original number. B is to what power

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    Default Re: SUPER SIMPLE QUESTION!!!

    Take a look at the Java Platform SE 6 class. Most notably the pow method.

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    Default Re: SUPER SIMPLE QUESTION!!!

    I always write squares out (in my mind this is faster and more accurate, but not by much)

    Mmm, PIE. It's actually PI, and you can use Math.PI for the floating point representation of this number. Also, in Java you must explicitly spell out everywhere you're performing a multiplication/add/etc.

    double a = 3;
    double b = 3a; // error
    double b = 3 a; // error
    double b = 3 * a; // correct

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    Default Re: SUPER SIMPLE QUESTION!!!

    Volume of Cylinder = PI(radius)2(power 2) * height
    Surface Area of Cylinder = 2 PI radius * height

    ok so im confused on why my teacher would give me the above as a formulas. at my level of math and java programming the above makes no sense.. i can decipher the top one. but 2 pi radius * height.. umm wtf

    so its 2 * pi * radius * height? Why have one multiplication symbol and not the rest?

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    Default Re: SUPER SIMPLE QUESTION!!!

    Your anwser should look like this

    int height = 2;
    int radius = 3;
    double volume = Math.PI * (Math.pow(radius, 2) )* height;
    Last edited by Brt93yoda; September 2nd, 2010 at 10:21 PM.

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    Default Re: SUPER SIMPLE QUESTION!!!

    It isn't in parenthesis.. look at volume. o well, i got it fiqured out, i think my teachers kind of mean tho. THanks for the help everyone.

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    Default Re: SUPER SIMPLE QUESTION!!!

    Did you see my above post?

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