The points plotted below satisfy a polynomial equation. In what range(s) of x-values must there be a root of the graph? Check all that apply.

Question

http://media.apexlearning.com/Images/200708/28/98610190-195d-44fe-b83f-dcb5599221ca.gif

Answer 1

Since f(x) is a polynomial function, f(x) is continuous, that is, the graph has no gaps or jumps.    

 

If f(a) and f(b) have opposite signs, then f(x) has at least

one root (x-intercept)  between x = a and x = b.