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alexb
Charter Member
1866 posts
Jul-24-06, 06:48 AM (EST)

"spurious math"

 I have recently come across a shallow equality with a deep appearance and little sense:[e][π] + [π] = [π][e] + [e]I'd be grateful for more examples.Thank you,Alex

mr_homm
Member since May-22-05
Jul-24-06, 00:05 AM (EST)

1. "RE: spurious math"
In response to message #0

 Well, there's the fake "proof by example" that square root is linear:[sqrt(2)] + [sqrt(2)] = [sqrt(4)][sqrt(3)] + [sqrt(3)] = [sqrt(6)][sqrt(8)] + [sqrt(8)] = [sqrt(16)]This works the same way as your example, by using the greatest integer operation to change the apparent value to something trivial.Here's another:Let I be the iteration operator, so that I(o,n) iterates the operation o n times. For an arbitrary ring G and a in G, let a+ be left addition by a and a* be left multiplication by a. Theorem: For the real number field, there is a unique element a for which for which the additive and multiplicative operations coincide, i.e., I(a+,1)(a) = I(a*,1)(a).Proof:2+2 = 4 = 2*2.QEDI just made this last one up on the spot. Hope it's amusing.Stuart Anderson

alexb
Charter Member
1866 posts
Jul-25-06, 00:06 AM (EST)

2. "RE: spurious math"
In response to message #1

 Very good. Thank you.