Answer
$\dfrac{3}{4} \ sq. unit$
Work Step by Step
We are given that $f(x)=\int_1^2 \dfrac{x}{2} \ dx$
Here. the area of a trapezoid is equal to $A= \int_1^2 ( \dfrac{x}{2} ) \ dx$
$=\dfrac{1}{2} \times (a+b) \times Height$
$=\dfrac{1}{2} (\dfrac{1}{2}+1)(1)$
Thus, $\int_1^2 (\dfrac{x}{2}) \ dx=\dfrac{3}{4} \ sq. unit$
