Question $1$

Let f$($x$)=$ln$(1+$x$).$ To find the area under the graph of f$($x$)$ over $1,9,$ we need to calculate the definite

integral $\backslash$int$\_1^9$ f$($x$)$dx$.$ Find the following approximations using the summation notation. $($You don't need

to calculate the value of the approximation, but you need to justify any quatities you defined in your

answer.$)$

$(1)$ L$\_(10)$ : the left$-$endpoint approximation using $10$ subintervals.

$(2)$ R$\_(10)$ : the right$-$endpoint approximation using $10$ subintervals.