we are asked to use synthetic division to divide f(x) by (x - k) where k = -1. This is performed as follows:
-1 | 4 -2 2 4
| -4 6 -8
-----------------------------
4 -6 8 -4
Given that k < 0 and the values in the bottom row of the synthetic division alternate between non-negative and non-positive, then x = -1 is a lower bound for the real zeros of the function f(x).
In mathematics, the reciprocal, or multiplicative inverse, of a number x is the number which, when multiplied by x, yields 1. It is denoted 1/x or x-1.