Multiplying Polynomials Calculator

Multiply two polynomials with step-by-step solutions and detailed explanations

Polynomial Multiplication Calculator

Formula

P(x) × Q(x) = ?
Each term in P(x) is multiplied by each term in Q(x)

First Polynomial P(x)

Highest power of x in the polynomial

Coefficients (from highest to lowest degree):

P(x) =

x^2+2x+3

Second Polynomial Q(x)

Highest power of x in the polynomial

Coefficients (from highest to lowest degree):

Q(x) =

x-2

Result

x^3-x-6
Product of the two polynomials (degree 3)

Result Coefficients

x^3
1
x
-1
constant
-6

Step-by-Step Solution

Step 1: Original Problem
P(x) × Q(x) = (x^2+2x+3) × (x-2)
Step 2: Apply Distributive Property
Each term in the first polynomial must be multiplied by each term in the second polynomial.
Step 3: Individual Term Multiplications
(x^2) × (x) = x^3 (x^2) × (-2) = -2x^2 (2x) × (x) = 2x^2 (2x) × (-2) = -4x (3) × (x) = 3x (3) × (-2) = -6
Step 4: Combine Like Terms
Add all terms with the same power of x: x^3 -x -6
Step 5: Final Answer
x^3-x-6

Example Problems

Example 1: Multiplying Binomials

Problem: Multiply (x + 2)(x + 3)

Solution:

  • x × x = x²
  • x × 3 = 3x
  • 2 × x = 2x
  • 2 × 3 = 6

Combine like terms: x² + 3x + 2x + 6 = x² + 5x + 6

Example 2: Polynomial × Binomial

Problem: Multiply (x² - 2x + 1)(x + 4)

Solution:

Multiply each term in the first polynomial by each term in the second:

  • x² × x = x³
  • x² × 4 = 4x²
  • (-2x) × x = -2x²
  • (-2x) × 4 = -8x
  • 1 × x = x
  • 1 × 4 = 4

Combine like terms: x³ + 4x² - 2x² - 8x + x + 4 = x³ + 2x² - 7x + 4

Example 3: Two Trinomials

Problem: Multiply (x² + x + 1)(x² - x + 1)

Solution:

This is a special case that results in:

Result: x⁴ - x² + x² + 1 = x⁴ + 1

Note: Many middle terms cancel out in this symmetric case

Multiplication Rules

Distributive Property

Each term in the first polynomial multiplies each term in the second polynomial

Combine Powers

When multiplying terms with the same variable, add the exponents: x^a × x^b = x^(a+b)

Combine Like Terms

After multiplication, add coefficients of terms with the same power

Degree Rule

The degree of the product equals the sum of the degrees of the factors

Key Concepts

Monomial

A single term (e.g., 3x², -5, 2xy)

Binomial

Two terms (e.g., x + 2, 3x² - 5x)

Trinomial

Three terms (e.g., x² + 3x + 2)

Polynomial

Expression with multiple terms involving variables with non-negative integer exponents

Degree

Highest power of the variable in the polynomial

Quick Tips

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Use the distributive property: multiply each term by every other term

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Add exponents when multiplying variables: x² × x³ = x⁵

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Multiply coefficients normally: 3x × 4x = 12x²

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Always combine like terms in the final answer

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Write answers in descending order of powers

Understanding Polynomial Multiplication

What are Polynomials?

A polynomial is an algebraic expression consisting of variables and coefficients, involving only non-negative integer powers of variables. Examples include 3x² + 2x - 5 and x⁴ - x² + 1.

The Distributive Property

When multiplying polynomials, we apply the distributive property: each term in the first polynomial must be multiplied by each term in the second polynomial.

(a + b)(c + d) = ac + ad + bc + bd

Step-by-Step Process

Follow these systematic steps to multiply any two polynomials:

1

Apply Distributive Property

Multiply each term in first polynomial by each term in second

2

Multiply Terms

Multiply coefficients and add exponents for like variables

3

Combine Like Terms

Add coefficients of terms with same variable powers

4

Arrange in Standard Form

Write result in descending order of powers

Special Cases

Monomial × Polynomial

Multiply the monomial by each term in the polynomial

3x(x² + 2x - 1) = 3x³ + 6x² - 3x

Binomial × Binomial

Use FOIL method or distributive property

(x+a)(x+b) = x² + (a+b)x + ab

General Case

Apply distributive property systematically

Result degree = sum of input degrees