# Science:Math Exam Resources/Courses/MATH220/December 2009/Question 09 (a)

MATH220 December 2009
Other MATH220 Exams

### Question 09 (a)

Find the supremum, maximum, infimum, and minimum of the following subsets of ${\displaystyle \mathbb {R} }$ (if they exist). If they do not exist write "none". You do not need to justify your answers.

set supremum maximum infimum minimum
${\displaystyle \{x\in \mathbb {R} \quad {\textrm {s.t.}}\quad {}7
${\displaystyle \{x\in \mathbb {Q} \quad {\textrm {s.t.}}\quad {}x^{2}<3\}}$
${\displaystyle \{x\in \mathbb {Z} \quad {\textrm {s.t.}}\quad {}x^{2}<3\}}$
${\displaystyle \bigcap _{n=1}^{\infty }\left(1-{\frac {1}{n}},4+{\frac {1}{\sqrt {n}}}\right)}$
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