1) In this Sequence, let's rewrite it to better see it.
[tex]\begin{gathered} a_1=\text{ }(1\text{ +}\frac{1}{2})\text{ =}\frac{3}{2} \\ a_2=\text{ (}1+\frac{1}{3}\text{ ) =}\frac{4}{3}\text{ } \\ a_{3\text{ }=\text{ }}(1+\frac{1}{4})=\frac{5}{4} \end{gathered}[/tex]If we subtract we see
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