One more

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One more

by netneoaaa » Thu Jul 05, 2007 3:52 am
if z^n=1, what is z

1. n is nonzero integer
2. z>0

ans : both c

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by jrbrown2 » Thu Jul 05, 2007 7:07 am
z^n = 1
(1)
If n is a non-zero integer z could be 1 or -1.
eg. -1^2 = 1, 1^2 = 1....... insufficient

(2) If z > 0, then z could be any value as long as n = 0. (any # to the power of zero = 1)........ insufficient

Together
From statement 1 we know that z is 1 or -1 and from state ment 2 we know that z >0. The only value that would make both statements true would be 1.

Hence, C