If z^n = 1, what is the value of z?
(1) n is a non zero integer
(2) z > 0
The OA is C.
Why is not sufficient the first statement alone? Could anyone show me a good approach to solve this DS question? Thanks in advance.
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If z^n = 1, what is the value of z?
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Statement 1:M7MBA wrote:If z^n = 1, what is the value of z?
(1) n is a non zero integer
(2) z > 0
Case 1: z=1 and n=1, with the result that z^n = 1¹ = 1
Case 2: z=-1 and n=2, with the result that z^n = (-1)² = 1
Since z can be different values, INSUFFICIENT.
Statement 2:
Case 1: z=1 and n=1, with the result that z^n = 1¹ = 1
Case 2: z=2 and n=0, with the result that z^n = 2� = 1
Since z can be different values, INSUFFICIENT.
Statements combined:
Only Case 1 satisfies both statements.
In Case 1, z=1.
SUFFICIENT.
The correct answer is C.
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My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
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