if z^n=1, what is z
1. n is nonzero integer
2. z>0
ans : both c
One more
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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
(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