For Exercise:(a) Use a graphing utility to graph the equation.(b) Use a graphing utility,...

For Exercise:

(a) Use a graphing utility to graph the equation.

(b) Use a graphing utility, as in Example 5, to estimate to one decimal place the x-intercepts.

(c) Use algebra to determine the exact values for the x-intercepts. Then use a calculator to check that the answers are consistent with the estimates obtained in part (b).

EXAMPLE 5 Finding approximate and exact values for x-intercepts

y = 2x3 − 5x