Is a an integer?
(1) a^3 is an integer.
(2) The cube root of a is an integer.
OA B
Source: Veritas Prep
Is a an integer?
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Statement 1 tells us that a is the cube root of some integer. Sometimes cube roots of integers are themselves integers, and sometimes not, so Statement 1 is not sufficient.
Statement 2 tells us that the cube root of a is an integer, so a itself will be the cube of an integer, and must therefore be an integer. So Statement 2 is sufficient and the answer is B.
Statement 2 tells us that the cube root of a is an integer, so a itself will be the cube of an integer, and must therefore be an integer. So Statement 2 is sufficient and the answer is B.
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From 1:BTGmoderatorDC wrote:Is a an integer?
(1) a^3 is an integer.
(2) The cube root of a is an integer.
OA B
Source: Veritas Prep
We don't know the orientation of a, what if it was
\(a = 3^{1/3}\), we satisfy 1, but answer to the question will be a No
\(a = 3\), we satisfy 1, and answer the question a Yes
From 2:
The cube root of a is an integer.
This will always be true, \(a^{1/3} = 3^{3\cdot 1/3} =\) Yes
Therefore, __B__