Interesting theorem!
There's only one problem: you cant divide by zero! ;)
Still, you might be able to fool some less observant high school algebra teachers for a few minutes with this one! Or if you ARE the high school math teacher, this would be a great way to stupefy legions of struggling math students.
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Theorem:
All numbers are equal.
Proof:
Choose arbitrary a and b, and let t = a + b.
(a + b)(a - b) = t(a - b)
a^2 - b^2 = ta - tb
a^2 - ta = b^2 - tb
a^2 - ta + (t^2)/4 = b^2 - tb + (t^2)/4
(a - t/2)^2 = (b - t/2)^2
a - t/2 = b - t/2
a = b
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