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RE: What is the limit? (was RE: multi-homing fixes)

  • From: Alex Bligh
  • Date: Wed Aug 29 14:20:54 2001


Roeland,

--On Wednesday, 29 August, 2001 10:13 AM -0700 Roeland Meyer <[email protected]> wrote:

|>   Draw two curves, the first y=x/2, the second y=x^2
|> Move the value of x for y=1 for the first curve left by 2, 5 or 10
|> and it will still be surpassed by the second curve.
|> You will even see this for a second curve of y=x*2 or y=x.

Prove it.
Prove that y1=A(x^2)+Bx+C always exceeds y0=Dx+E
for positive A and D, for all x>x0 for
some value x0?

Um, y1-y0 = A(x^2) + (B-D)x + (C-E)   [1]

This is a positive parabola with standard
solutions. To the right of it's higher root,
it's always positive, so y1>y0.

Now, I take it you don't want proof of
the roots to quadratic equations?

--
Alex Bligh