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Can someone please clarify this

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Can someone please clarify this

by sanaa.rizwan » Mon Apr 29, 2013 11:19 am
Id d is a positive integer, is √d an integer

1.d is a square of an integer
2.√d is the square of an integer

The correct answer is D

I understand how statement 2 is sufficient, But how is statement 1 sufficient

if d = 2^2 = 4 then √4 = integer
but
if d = 1^2 = 1 then √1 is not an integer

so statement 1 is not sufficient
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by srcc25anu » Mon Apr 29, 2013 11:29 am
St1 says d is square of an integer. where you have considered d = 1*2, that is incorrect as 2 is not a square of any integer. root2 is not an integer.
if you consider D to be integer sqaures like 1,4,9,16,25 .... you will always find that rootD is an integer (1,2,3,4,5 ... ) for the above case

Hence 1 is sufficient also.
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by Anju@Gurome » Mon Apr 29, 2013 11:32 am
sanaa.rizwan wrote:if d = 1^2 = 1 then √1 is not an integer
Take a break. I think you are over-stressing. :)
√1 = 1 is an integer.
sanaa.rizwan wrote:If d is a positive integer, is √d an integer

1. d is a square of an integer
2. √d is the square of an integer
Statement 1: If d is a square of an integer, square root of d must be an integer.

Sufficient

Statement 2: Square of an integer is always an integer.
So, √d is an integer.

Sufficient

The correct answer is D.
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by Blue_Skies » Mon Apr 29, 2013 2:52 pm
Id d is a positive integer, is √d an integer

1.d is a square of an integer
2.√d is the square of an integer

The correct answer is D

I understand how statement 2 is sufficient, But how is statement 1 sufficient

if d = 2^2 = 4 then √4 = integer
but
if d = 1^2 = 1 then √1 is not an integer

so statement 1 is not sufficient

We are given d is a positive integer and asked to find out if root d is an integer.
1)For your questions : root 1 is 1 which is an integer. Hence A is sufficient.
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