Chapter 2.4, Problem 61PE

For Exercises 59-64, (See Example 9)

a. Determine if the upper bound theorem identifies the given number as an upper bound for the real zeros of $f\left(x\right)$ .

b. Determine if the lower bound theorem identifies the given number as a lower bound for the real zeros of $f\left(x\right)$ .

$\begin{array}{l}f\left(x\right)=8x^3-42x^2+33x+28\\ \text{a}\text{. }6\\ \text{b}\text{. }-1\end{array}$