Quick, what numbers x satisfy:
abs( x-2 ) < 1
How does Maple answer this?
solve( abs( x-2 ) < 1, x );
Now, change the RHS to 1. (floating-point 1):
solve( abs(x-1) < 1., x );
RealRange(1., Open(2.)), RealRange(Open(0.), Open(1.))
Of course, these two intervals can be combined to the one interval. Maple 10 did not have this problem. (I will explain what Maple 11 is doing later, I want the next paragraph to appear in the truncated version of this post.)
This issue is important for those of us trying to use Maple in the classroom. While it's not difficult to explain what is going on, the point is that this is not the mathematics I am trying to teach and these issues are a distraction.