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Looking for an equation expressed algebriacally that answers the following

  1. Jun 28, 2009 #1
    Given an XY graph where the horizontal line is X and the vertical line is Y and their intersection is zero, if A = 0,1 (a horizontal line one increment above the X axis), I want to know the formula that correctly expresses the value of B if B started at 0,0 and always approaches infinite A at a uniformly constant rate.
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  3. Jun 28, 2009 #2


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    a.k.a. The Cartesian Plane. Probably the most widely known and frequently used coordinate system in Mathematics :smile:

    Everything is very clear cut, until...
    eh? Please elaborate.
  4. Jun 28, 2009 #3


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    You just said "A= 0, 1", a notation I would have interpreted as the point (0, 1) but then you say "(a horizontal line one increment above the X axis)" which is the line y= 1. In either case, what do you mean by "approaches infinite A"? A is NOT "infinite". Do you mean "is asymptotic to y= 1 as x goes to infinity"? And what do you mean by "approaches at a uniformly constant rate"? That d(y-1)/dx= constant? That's impossible. Any solution to that is linear and cannot be asymptotic to y= 1. d(y-1)/dx= constant*(y-1) is possible. Calling the constant rate [itex]\alpha[/itex], any solution to that is of the form
    [tex]y=1+ Ce^{\alpha x}[/tex]
    which approaches y= 1 at constant rate [itex]\alpha< 0[/itex].
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