Gmat prep - real number question

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Re: Gmat prep - real number question

by dtweah » Tue May 05, 2009 5:19 pm
fercho81 wrote:Thanks in advance for replying to this post.

See the attached
There is nothing to really solve in this problem. They are testing whether you know the square root of the fist few intergers and some ideas about the root of numbers above or below 1.

Square root of 3 is 1.732. Since 1.732 >1, you know its square root will be >1 but < 1.732. The square root of numbers between 0 and 1 is greater than such numbers.( 0.5^.5 >.5)So imagine this square to be some number greater than 1 but less than 1.732. 2- this number is >1. Again the square root of any number greater than 1 is itself greater than 1, so 3 is well defined. If 3 is defined so is 2. 1 and 4 are trivial. Leaving 5 which you don't have to analyze. You know the square root of 5 is >2 so you will have an imaginary number under the radical.