📐 Rational Zeros Calculator

Find possible rational zeros using Rational Root Theorem

For polynomial: ax^n + ... + c

How to Use This Calculator

1

Enter Leading Coefficient

Type the coefficient of the highest-degree term (a). For 2x³ + 5x + 6, enter 2.

2

Enter Constant Term

Type the constant term (c). For 2x³ + 5x + 6, enter 6.

3

Click Find

See all possible rational zeros using the Rational Root Theorem.

Formula

Possible Rational Zeros = ± (factors of c) / (factors of a)

For polynomial: a_nx^n + ... + a₁x + a₀

Example 1: x³ - 2x² - 5x + 6 = 0

Leading coefficient (a) = 1, Constant (c) = 6

Factors of 6: ±1, ±2, ±3, ±6

Factors of 1: ±1

Possible zeros: ±1/1, ±2/1, ±3/1, ±6/1

Possible zeros: 1, -1, 2, -2, 3, -3, 6, -6

Example 2: 2x³ + 5x + 1 = 0

a = 2, c = 1

Possible zeros: ±1/1, ±1/2

Possible zeros: 1, -1, 1/2, -1/2

About Rational Zeros Calculator

The Rational Zeros Calculator uses the Rational Root Theorem to find all possible rational zeros of a polynomial. This theorem states that any rational zero of a polynomial must be of the form p/q, where p divides the constant term and q divides the leading coefficient.

When to Use This Calculator

  • Finding Roots: Get all candidate rational roots
  • Factoring: Start factoring process
  • Polynomials: Solve higher-degree equations
  • Algebra: Polynomial division and factoring

Why Use Our Calculator?

  • Complete List: Shows all possible rational zeros
  • Fast Results: Instant calculation
  • Educational: Understand Rational Root Theorem
  • Free Tool: No registration

Key Points

  • Not all possible zeros are actual zeros
  • Test each candidate by substitution
  • Works only for polynomials with integer coefficients
  • May include duplicates and need simplification

Tips

  • Start with simplest candidates (usually ±1)
  • Use synthetic division to test zeros
  • Even irrational zeros won't appear in this list

Frequently Asked Questions

What is the Rational Root Theorem?

A theorem stating that any rational zero must be p/q where p divides the constant term and q divides the leading coefficient.

Are all listed values actual zeros?

No! This gives possible candidates. You must test each one to see if it's actually a zero.

What about irrational zeros?

This calculator only finds rational candidates. Irrational zeros like √2 won't appear in the list.