Give an example of a set which has least upper bound 5 but contains no element x satisfying x5. Let A={x: x^2+3x+20}. Prove that this set is...

1. Give an example of a set which has least upper bound 5 but contains no element x satisfying x<5.2. Let A={x: x^2+3x+2<0}. Prove that this set is non-empty and bounded above. What is the least upper bound?Is it bounded below?

:−1= { | = 5} = {5}5 ℎ ℎ ℎ &lt;5 ∈ 2={ | + 3 + 2 &lt; 0} ℎ +3 +2&lt;0 =&gt; ( + 2)( + 1) &lt; 0= −2ℎ −1 +3 +2&lt;0ℎ=&gt; = { |−2 &lt; =&gt;&lt; −1 ℎ ∈ (−2,1)...