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omegaella4u
11-23-2004, 01:45 PM
y=x^2 + 1/x

0<x<99

Col A Col B
y 100.

Answer D

surans
11-23-2004, 01:54 PM
since x is not an integer, take weird nos for x and check

for ex, if x=2 then y=4+1/2 = 4+.5 = 4.5 <100 thus b>a
if x=.01 then y=(.01)^2+ 1/.01 = .0001+100 = 100.0001 >100 thus b<a

so D.

danielman
11-23-2004, 01:54 PM
y=x^2 + 1/x

0<x<99

Col A Col B
y 100.

Answer D

note that when x is aproaching to 0, the term 1/x is bigger and bigger (in fact, it could be as bigger as you want) while x^2 is aproaching to 0. On the other hand, when x=1, y = 0.

So, the expression could be either much bigger or lower than 100. Answer = D

omegaella4u
11-23-2004, 01:57 PM
thanks guys, its clear now.