2. Dividing Polynomials
Sign In
Look for changes in the sign of f(x).
Between -1 and 0, and between 2 and 3.
To determine the location of the zeros of a quadratic function using the given table, we need to look for changes in the sign of f(x).
x | -2 | -1 | 0 | 1 | 2 | 3 | 4 | 5 |
---|---|---|---|---|---|---|---|---|
f(x) | 6 | 1 | -3 | -5 | -3 | 1 | 6 | 14 |
We see in the table that f(-1)=1, and that f(0)=-3. The function here goes from positive to negative. Therefore, there must be a zero between -1 and 0.
Similarly, look at f(2)=-3 and f(3)=1. Since the function here goes from negative to positive, there must be a zero between 2 and 3.