# Math Help - Interior Sets

1. ## Interior Sets

Find the interior and boundary of each of the follwing sets:

a. [0,1)
b. Q
c. R\Q
d. R
e. (-inf,-2) U {1/n: n is a natural} U [1, inf)

I think a) (0,1) b) empty set c) empty set

2. Originally Posted by Jdg6057
Find the interior and boundary of each of the follwing sets:

a. [0,1)
b. Q
c. R\Q
d. R
e. (-inf,-2) U {1/n: n is a natural} U [1, inf)

I think a) (0,1) b) empty set c) empty set
Yes, that's right so far. d) $\mathbb{R}$ e) $(-\infty,-2)\cup(1,\infty)$

Note that $int(A)\cup bound(A)=cl(A)$, so what are the boundary points of each set?