Re: maths-functions

Posted by ritu on Oct 12, 2011; 12:55pm
URL: http://discussion-forum.276.s1.nabble.com/maths-functions-tp6880797p6884869.html

hey vasudha...bang on...ur ans is correct..........
see firstly...explain me one thing..since whole expression is under the root sign so it has to be >=0......so as u said either both numerator and denominator should be >0 or both <0....this means we have following cases.............
1. if both positive then........mod x <=1 and mod x<2...COMMON AREA ON NUMBER LINE IS...mod x <1
2.if both negative.......mod x >=1 and mod x >2......COMMON AREA ON NUMBER LINE IS  mod x >2......


NOW....MOD X <=1 MEANS X<=1 OR X>= (-1)......so common area is [-1,1]

MOD X>2..........MEANS  X>2....OR  X<(-2).....BUT IN THIS CASE THERE'S NO COMMON AREA ON REAL LINE.....X>2....AND   X<(-2). BEING DISJOINT SETS......SO TATS WHY U HAVE TAKEN THE UNION OF THESE 3 AREAS---ie.....[-1,1] U  (-infinity,-2)   U   (2,infinity)??????????is this is the whole logic behind ur answer....??????m sry for this long query....:)))