jeevan.Gk wrote:Is n an integer ?
1. n^2 is an integer.
n^2=3 n is not integer
n^2=4 n is integer
insuf
2. Sqrt (n) is an integer
4 is integer so is 2
144 is integer so is 12
SUF
B
N integer
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- logitech
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LGTCH
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cramya
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The point to note is if n^2 is an integer it does not mean n is always an integer. It may or may not be
n = sqrt(2) n^2->INT n->not an INT
n=2 n^2->integer n->integer
For sqrt(n) to be an integer n has to be an integer
n = sqrt(2) n^2->INT n->not an INT
n=2 n^2->integer n->integer
For sqrt(n) to be an integer n has to be an integer
- logitech
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once you feel uncomfortable with the concepts try this methodjeevan.Gk wrote:Is n an integer ?
1. n^2 is an integer.
2. Sqrt (n) is an integer
use numbers and check with the question stem
1. n^2 is an integer.
you know n^2 is always positive so choose the first 5 positive numbers
1 - Not integer when you take its root
2 - Not integer when you take its root
3 - Integer when you take its root YOU CAN STOP HERE since you have a YES and NO , which means insuf
4
5
2. Sqrt (n) is an integer
so choose the first five squares
1 4 9 16 and 25 and all of them will give you an integer when you find their root.
SO SUF
LGTCH
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"DON'T LET ANYONE STEAL YOUR DREAM!"
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"DON'T LET ANYONE STEAL YOUR DREAM!"

















