Polynomial Division

6-7Polynomial Long Division

Overview

Divide polynomials by polynomials using long division, just like with whole numbers.

Key ideas

  • Arrange both polynomials in descending order; fill missing terms with 0.
  • Divide leading terms; multiply, subtract, bring down.
  • Stop when the remainder’s degree is less than the divisor’s.

Worked examples

Example 1

Problem. Divide (x^2 + 5x + 6) by (x + 2).

Solution. Quotient x + 3, remainder 0. So result = x + 3.

Practice

Try each one. Click Show answer when ready.

  1. 1.

    Divide (x^2 + 7x + 12) ÷ (x + 3).

  2. 2.

    Divide (x^2 − 9) ÷ (x − 3).

  3. 3.

    Divide (2x^2 + 7x + 3) ÷ (x + 3).

Challenge problems

A little tougher — great for test prep. Click Show answer when ready.

  1. 1.

    Divide: (x³ + 2x² − 5x − 6) ÷ (x + 1).

  2. 2.

    Divide: (2x³ − 5x² + 3x − 1) ÷ (x − 2).