I am trying to prove the following. I have a solution below. Can you tell if I am on the right track. P.S. I am doing calculus after 14 yrs so I am very rusty and probably sound stupid(adsbygoogle = window.adsbygoogle || []).push({});

1- Let T be a non-empty subset of R. Assume T is bounded below. Consider the set S = -T = {-t|t is an element of T}. Show that S is bounded above

Solution

a- Let -a= inf(T)

b- -(-a) is also an element of S (because it is a mapping)

c- Let b element of S

And this is where I am getting stuck at.

Intuitively, I know that a > b and it will be the supremum in S but I cannot prove it.

Thanks

Asif

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# Homework Help: Supremum & inifimum

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