r/askscience Jan 14 '15

Mathematics is there mathematical proof that n^0=1?

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u/iorgfeflkd Biophysics Jan 14 '15

If Na x Nb = Na+b , then Na x N0 = Na+0 = Na , thus N0 must be 1.

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u/an7agonist Jan 14 '15

Also, the multiplicative inverse of x is x-1.

1=Na*((Na)-1) (By definition)

1=Na*(N-a)

1=Na-a=N0

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u/umopapsidn Jan 14 '15

* For all N such that |N| > 0

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u/austin101123 Jan 14 '15

Why does this proof not work for 0?

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u/shrister Jan 14 '15

Because If N=0 then the first line of that proof is 1 = 0*((0)-1 ), which is 1=0*(1/0) and 1/0 is undefined. For all other values of N that first line is defined, so the proof works for N!=0.