Friday, September 10, 2010

Is x^2 greater than x?

1)x^2 is greater than 1.
2)x is greater than -1.



1) implies either x<-1 or x>1 (key is its being compared with '1' not '0' to get rid of the fractions that are <1.>

2) not sufficient. Take values 1/2 and 2 to verify.




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