Recent content by y2kevin

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    Undergrad Help simple 2nd order linear ODE

    Hi, could anyone give me a hint on what method to use to solve this ODE: v''+(2/t)v'+(b)v=0, b is a constant and v=v(t). Most of my ODE training resolves around how to solve the above equation with constant coefficients. AND all of my reference books say that "the nonconstant case is...
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    Show Isomorphism of ZxZ/<(a,b)> to Z if gcd(a,b)=1

    any ideas?
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    Show Isomorphism of ZxZ/<(a,b)> to Z if gcd(a,b)=1

    Homework Statement Show that ZxZ/<(a,b)> is isomorphic to Z if gcd(a,b)=1. The Attempt at a Solution I thought I had an idea but apparently I don't. I reasoned this geometrically. For ZxZ/<(1,a)> (for all a in Z) can be graphed as a line hitting points (k,a*k) in the x-y plane. If...
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    Weird group isomorphism problem

    anyone?
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    Weird group isomorphism problem

    It came up during class following the problem ZxZ/<(7,37)>. Apparently these two problems share some similar characteristics.
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    Weird group isomorphism problem

    Homework Statement Show that the group Z/<(a,b)> is isomorphic to Z if gcd(a,b)=1. Find generators of Z/<(a,b)>. 2. Relevant information Please note that the question is asking for Z/<(a,b)>, not ZxZ/<(a,b)>. I am having trouble understanding the meaning behind <(a,b)> as a subgroup of...