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Truth in inequalities
Posted:
Jun 14, 2001 2:50 AM


Hi group,
Can someone explain the logic of the following:
x < Infinity returns x < Infinity while x  Infinity < 0 returns True
I should mention that I am aware of the fact that x  Infinity simplifies automatically to Infinity which is then compared to 0 and found wanting. The issue I'm raising is why should a CAS that has xInfinity < 0 return True not also return True for the x < Infinity? One awkwardness of having this difference of behavior can be seen in the example,
MyFunction[x_,y_]/;(x<y) := blah
and
MyFunction[x_,y_]/;(xy<0) := blah
do not do the same thing when, say, y=Infinity.
Just curious :)
Jack



