- #1
analysis001
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Homework Statement
What is the set of the unit ball centered at 0 = (0,0) in the (x1, y2)-plane, where d1(x,y)=|x1-y1|+|y1-y2| is in the metric space (R2, d1)
Homework Equations
An open ball is Br(x)={y[itex]\in[/itex]X|d(x,y)<r}
The Attempt at a Solution
I know the solution is this: B1(0)={(x1,x2)[itex]\in[/itex]R2 | |x1| + |x2| < 1}
but I'm not sure how to get that answer. Here is what my answer would have been (by the definition of the open ball):
B1(0)={y[itex]\in[/itex]R2| |-y1|+|x2|<1}
I know that's wrong. So basically, could someone just explain the correct answer? Thanks!