If x is an integer greater than 1, is x equal to 2^k for some positive integer k?
(1) x has only one prime factor.
(2) Every factor of x is even.
The OA is B .
I don't have this DS question very clear. Experts, can you assist me here? Please.
If x is an integer greater than 1
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We are given that if x (an integer) > 1, is x = 2^k; where k is some positive integerM7MBA wrote:If x is an integer greater than 1, is x equal to 2^k for some positive integer k?
(1) x has only one prime factor.
(2) Every factor of x is even.
The OA is B .
I don't have this DS question very clear. Experts, can you assist me here? Please.
(1) x has only one prime factor.
If x = 2^1 = 2 (only one prime factor), the answer is Yes; however if x = 3 (only one prime factor), then the answer is No. Insufficient.
(2) Every factor of x is even.
The statement should have been, "Every factor of x other than 1 is even."
If we assume that x = 2^k*3^m, then it is not possible since this will render odd factors too; it will invalidate the statement.
The only possible case is x = 2^k; where k is some positive integer. Sufficient.
The correct answer: B
Hope this helps!
-Jay
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