Factor Polynomials with Complex Roots

Videos, solutions, and lessons to help High School students learn how to extend polynomial identities to the complex numbers. For example, rewrite x2 + 4 as (x + 2i)(x – 2i).

Common Core: HSN-CN.C.8

Related Topics:
Common Core (The Complex Number System)

Common Core for Mathematics

Factor Expressions Using Complex Numbers
How to factor expressions using complex numbers.
Factorizing polynomials with complex numbers.

Polynomial Function with Complex Zeros (Three Ways)
Starting with a third-degree polynomial with one known complex zero, how can you find the other zeros? This video explores three interesting options, utilizing polynomial division, synthetic division, the quadratic formula, and square roots of complex numbers.
The Conjugate Pair Theorem - Example 1
This video shows that if we know a complex root, we can use that to find another complex root using the conjugate pair theorem.

Factor Polynomial Given a Complex / Imaginary Root
The Conjugate Pair Theorem - Example 2. In this video, I factor a 3rd degree polynomial completely given one known complex root.
How to find complex zeros of a polynomial function.

Real and Complex Polynomial Roots
Polynomial Roots- Real and Complex: This tutorial will teach you how to solve polynomials with complex roots. You will learn Descartes' rule of signs, the fundamental theorem of algebra and the conjugate pairs theorem.
Find the Zeros of a Polynomial Function with Imaginary Zeros
This video provides an example of how to find the zeros of a degree 3 polynomial function with the help of a graph of the function. The function has 1 real rational zero and 2 imaginary.

Find the Zeros of a Polynomial Function with Complex Zeros
This video provides an example of how to find the zeros of a degree 3 polynomial function with the help of a graph of the function. The function has 1 real rational zero and 2 complex zeros.
Find the Zeros of a Degree 4 Polynomial Function
This video provides an example of how to find the zeros of a degree 4 polynomial function with the help of a graph of the function. The function has 2 real rational zero and 2 complex zeros.

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