Answer
The right endpoints are
$$2.5, \quad 3, \quad 3.5, \quad 4, \quad 4.5, \quad 5$$
and the left endpoints are
$$2, \quad 2.5, \quad 3, \quad 3.5, \quad 4, \quad 4.5 $$
Work Step by Step
We have $\Delta x=\frac{5-2}{6}=0.5$; now the right endpoints are
$$2.5, \quad 3, \quad 3.5, \quad 4, \quad 4.5, \quad 5$$
and the left endpoints are
$$2, \quad 2.5, \quad 3, \quad 3.5, \quad 4, \quad 4.5 $$
See page 226 in the book for examples.