Recent content by PlasticOh-No

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    Mathematica Mathematica: take derivative in terms of original function

    Thanks for your reply. Just one thing - how do I undefine the original definition of f[x_,y_] ?? Thanks again
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    Mathematica Mathematica: take derivative in terms of original function

    Ok let me make this a little clearer. Let's say we have f[x_,y_]:=Exp[a*(x+y)] where a is some real parameter. Now we take D[f[x,y],x] which is equal to a*Exp[a*(x+y)]. How can I get Mathematica to give a result like a*f[x,y] Thank you in advance for you attention on this.
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    Mathematica Mathematica: take derivative in terms of original function

    Hello, Let's say we have f[x_,y_]:= whatever then we say expr1 = D[f[x,y],x] which is some complicated expression. How can we get the answer in terms of f[x,y]? That is, how can we get expr1 to look like: expr1 = f[x,y]*this term + pi*Sqrt[f[x,y]] + et cetera? Thanks Gurus
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    MATLAB MATLAB quad and difficulty with vector input

    Oops. Is this just a matter of using quadv instead of quad?
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    Why Doesn't Wet Paper Burn?

    The answer is because of the heat capacity of water, which is enormous. Energy applied to the paper gets used up in the warming and subsequent evaporation of the water. In a sense it's not really about "temperature," but rather about energy. So the reason water is used to put out a fire is...
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    MATLAB MATLAB quad and difficulty with vector input

    MATLAB "quad" and difficulty with vector input Hello all. Consider the following: function y = testf(x,a) y = sin(pi.*a.*x); ...and then we have a = 0.05:0.05:1; result1 = quad(@(x)testf(x, a),0,1) which crashes with ? Error using ==> times Matrix dimensions must agree...
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    Distribution of Product of Dependent RV's

    Arrg. Thanks Matey f_Z(z)=\int_{-\infty}^{\infty}f(x,z-x)dx Shiver me timbers How does one edit an old post? thanks
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    Distribution of Product of Dependent RV's

    I got it, it is Z=X+Y [tex] f_Z(z)=\int_{-\infty}^{\infty}f(x,z-x)dx [\tex] where f is the joint dist
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    Are there imaginary numbers other than i?

    by the way just wanted to note that my earlier post was not indented to seem argumentative, actually meant to be in the fashion of spirited discourse. In other words just trying to contribute. Thanks
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    Distribution of Product of Dependent RV's

    Hello again Can you give tips on also distribution of: sum or difference on random variables that are -possibly dependent -non Gaussian Thank you
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    Are there imaginary numbers other than i?

    Your points are wrong, and if taken as is, they are self-contradictory. You say: - Complex numbers are not "fake" - They are a simply a tool to solve problems - They most certainly are not real. They are fake. There is nothing naughty about admitting it. Kroenecker said that God made the...
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    Can e^{e^{e^{x}}} Be Simplified or Related to Hypergeometric Functions?

    Thanks everyone for your help. Yes, I meant e^{e^{e^{x}}}
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    Can e^{e^{e^{x}}} Be Simplified or Related to Hypergeometric Functions?

    Is there any way to simplify or clarify e^e^e^x ? Some sort of equivalence to a hypergeometric? How about e^e^x? Thanks
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    Distribution of Product of Dependent RV's

    I see. So we will be needing the joint distribution. My mistake, thank you very much for your help.
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