Let A be a nonempty subset of R. Define -A={-a: a A}. (a) Prove that if...

Question

Question

Let A be a nonempty subset of R. Define -A={-a: a $\epsilon$ A}.

(a) Prove that if A is bounded below, then -A is bounded above.

(b) Prove that if A is bounded below, then A has an infimum in R and inf A=-sup (-A).

Answer 1

Answer #1

A be a non empty subset of IR as - A=ş-aiata} 94 A is bounded below, then that mea, tata ? a merr such . - m > -a, VACA since

Answer 2

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