Real Numbers - Arithematic

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Real Numbers - Arithematic

by Sharms » Thu Mar 07, 2013 11:05 pm
For what value of x will the expression -2(x+1) - (x-2) not be a real number? *Please note that the entire expression highlighted in bold is under square root symbol... didnt know how to do that here***

A) -4
B) -3
c) -1
d) 0
e) .5

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by Anurag@Gurome » Thu Mar 07, 2013 11:09 pm
Sharms wrote:For what value of x will the expression √(-2(x+1) - (x-2)) not be a real number?
The expression will not be real only if the expression under root is negative.
So, (-2(x+1) - (x-2)) < 0
--> 2(x + 1) + (x - 2) > 0
--> 3x > 0
--> x > 0

Only possible answer is x = 0.5
[spoiler]
The correct answer is E.[/spoiler]
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