After performing synthetic division, you find the remaining zeros by setting the resulting quotient equal to zero and solving for x. This quotient will be a polynomial with a degree one less than the original polynomial.
Here's a breakdown of the process, incorporating information from the provided reference:
-
Perform Synthetic Division: Use synthetic division to divide the polynomial by a known zero (root). This will reduce the degree of the polynomial.
-
Write the Quotient: The result of the synthetic division gives you the coefficients of the new polynomial (the quotient). For example, the video reference mentions that if you start with an x cubed polynomial and perform synthetic division, the result will be an x squared polynomial.
-
Set the Quotient to Zero: Take the quotient polynomial and set it equal to zero. This creates an equation that you can solve for the remaining zeros.
- Example (from reference): If after synthetic division you have
1x² + 0x + 4
, you would set up the equationx² + 4 = 0
.
- Example (from reference): If after synthetic division you have
-
Solve for x: Solve the resulting equation for x. The solutions are the remaining zeros of the original polynomial.
- In the example above (
x² + 4 = 0
), you would subtract 4 from both sides (x² = -4
) and then take the square root of both sides (x = ±2i
). This means the remaining zeros are2i
and-2i
.
- In the example above (
In summary, synthetic division simplifies the polynomial, and then solving the resulting quotient allows you to find the remaining zeros.