Recent content by DianaSagita

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    Prove Graph Theory: All Vertices > 4, At Least 12 Degree 5

    Homework Statement If all vertices of planar graph have degrees greater than 4, prove if that graph has at least 12 vertices with degree of 5. Homework Equations d1+d2+...+dn= 2*m (m - number of edges, di-degree of i-vertex) f=2-n+m, f - number of faces, n-number of vertices The...
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    Number theory - prove if divisible by 2009

    Thank you, rasmhop! I understand now how to get it, your reply was helpful, cheers!
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    Number theory - prove if divisible by 2009

    Homework Statement Prove if there exists an integer whose decimal notation contains only 0s and 1s, and which is divisible by 2009. Homework Equations Dirichlet's box principle :confused: The Attempt at a Solution I'm new to number theory, and I'm aware that I do not have the...
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    Which primes p satisfy p^2|5^p^2+1?

    Well, thanks a lot, it seems correct! Meanwhile, I did it too... According to Euler's Theorem: 5^{p^{2}-p}\equiv 1(mod\ p^{2}) 5^{p^{2}}\equiv 5^{p}(mod\ p^{2}) 5^{p^{2}}-5^{p}\equiv 0(mod\ p^{2}) 5^{p^{2}}+1-(5^{p}+1)\equiv 0(mod\ p^{2}) So, if 5^{p^{2}}+1 is divisible by p2, then...
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    Which primes p satisfy p^2|5^p^2+1?

    Homework Statement First of all, hi everyone! I'm quite new in number theory, and need help on this one badly... Determine all prime numbers p so p2 divides 5p2+1. Homework Equations Euler's theorem: If a and m are coprimes then...
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    How Do You Find an Analytic Function Where the Argument is xy?

    I've got it! f(z)=e^{D_1(x)+D_{1num}-\frac{y^2}{2}+ixy} f(z)=e^{D_2(y)+D_{2num}+\frac{x^2}{2}+ixy} so... D_1(x)+D_{1num}-\frac{y^2}{2}=D_2(y)+D_{2num}+\frac{x^2}{2} D_1(x)=\frac{x^2}{2} D_2(y)=-\frac{y^2}{2} D_{1num}=D_{2num}=D and analytical function is...
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    How Do You Find an Analytic Function Where the Argument is xy?

    Thanks, and that's what I did... now I got... u=e^{-{\frac{y^2}{2}}}cos(xy)C_1 solving by u_y^' u=e^{\frac{x^2}{2}}cos(xy)C_2 solving by u_x^' C_1,C_2 constants C_1=e^{D_1},C_2=e^{D_2} so I have functions... f(z)=e^{D_1-\frac{y^2}{2}+ixy} f(z)=e^{D_2+\frac{x^2}{2}+ixy} How two...
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    How Do You Find an Analytic Function Where the Argument is xy?

    Well, I must find modulo... and this one you entered is not analytical function... :(
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    How Do You Find an Analytic Function Where the Argument is xy?

    1. This is something from complex analysis: Find the analytic function f(z)= f(x+iy) such that arg f(z)= xy. 2. w=f(z)=f(x+iy)=u(x,y)+iv(x,y) (*), w=\rho e^{i\theta} (**) Here are the Cauchy-Riemann conditions... \frac{\partial u}{\partial x}=\frac{\partial v}{\partial...
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    Solving for Volume in a Complex Figure: Ostrogradsky and Spherical Coordinates

    Volume Integral! Help! I need help with this: Find volume of figure bounded with surface (x^2+y^2+z^2+1)^2=8*(x^2+y^2) I tried Ostrogradsky, and spherical coordinate system with it, but I can't find boundaries... PLEASE! HELP ME!
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