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104 LearnersLast updated on September 15, 2025

Calculators are reliable tools for solving simple mathematical problems and advanced calculations like trigonometry. Whether you’re cooking, tracking BMI, or planning a construction project, calculators will make your life easy. In this topic, we are going to talk about complex root calculators.
A complex root calculator is a tool to find the roots of polynomial equations that have complex numbers as their solutions.
When an equation has no real roots, complex roots are often present.
This calculator makes finding these solutions much easier and faster, saving time and effort.
Given below is a step-by-step process on how to use the calculator:
Step 1: Enter the coefficients: Input the coefficients of the polynomial into the given fields.
Step 2: Click on calculate: Click on the calculate button to find the complex roots and get the result.
Step 3: View the result: The calculator will display the result instantly.
To calculate complex roots, we need to solve the polynomial equation using the quadratic formula or other root-finding methods.
The quadratic formula can provide complex solutions when the discriminant is negative.
For a quadratic equation ax² + bx + c = 0, the formula is: Roots = [-b ± sqrt(b² - 4ac)] / 2a
When b² - 4ac < 0, the roots are complex, expressed as:
Real part: -b / 2a Imaginary part: ± sqrt(abs(b² - 4ac)) / 2a
When using a complex root calculator, there are a few tips and tricks that can make it easier and help avoid mistakes:
Consider the polynomial's degree to anticipate the number of roots.
Verify the input coefficients for accuracy.
Use decimal precision to interpret the real and imaginary parts separately.
We may think that when using a calculator, mistakes will not happen.
But it is possible for errors to occur when using a calculator.
What are the complex roots of the equation x² + 4 = 0?
Using the quadratic formula: Roots = [-b ± sqrt(b² - 4ac)] / 2a
For x² + 4 = 0, a = 1, b = 0, c = 4: Discriminant = b² - 4ac = 0 - 16 = -16
Complex roots are: Roots = [0 ± sqrt(-16)] / 2 Roots = ± 2i
The discriminant is negative, indicating complex roots.
The roots are purely imaginary: ± 2i.
Find the complex roots for the polynomial equation x² + 2x + 5 = 0.
Using the quadratic formula: Roots = [-b ± sqrt(b² - 4ac)] / 2a
For x² + 2x + 5 = 0, a = 1, b = 2, c = 5:
Discriminant = b² - 4ac = 4 - 20 = -16
Complex roots are: Roots = [-2 ± sqrt(-16)] / 2 Roots = -1 ± 2i
The negative discriminant results in complex roots.
The roots are -1 ± 2i, combining real and imaginary parts.
Determine the complex roots of x² - 6x + 13 = 0.
Using the quadratic formula: Roots = [-b ± sqrt(b² - 4ac)] / 2a
For x² - 6x + 13 = 0, a = 1, b = -6, c = 13:
Discriminant = b² - 4ac = 36 - 52 = -16
Complex roots are: Roots = [6 ± sqrt(-16)] / 2 Roots = 3 ± 2i
The discriminant is negative, leading to complex roots 3 ± 2i.
Calculate the complex roots for the equation 2x² + 3x + 5 = 0.
Using the quadratic formula: Roots = [-b ± sqrt(b² - 4ac)] / 2a
For 2x² + 3x + 5 = 0, a = 2, b = 3, c = 5:
Discriminant = b² - 4ac = 9 - 40 = -31
Complex roots are: Roots = [-3 ± sqrt(-31)] / 4 Roots = -3/4 ± sqrt(31)i/4
The negative discriminant results in complex roots with both real and imaginary components.
What are the complex roots for the equation x² + x + 1 = 0?
Using the quadratic formula: Roots = [-b ± sqrt(b² - 4ac)] / 2a
For x² + x + 1 = 0, a = 1, b = 1, c = 1:
Discriminant = b² - 4ac = 1 - 4 = -3
Complex roots are: Roots = [-1 ± sqrt(-3)] / 2 Roots = -1/2 ± sqrt(3)i/2
The negative discriminant indicates complex roots: -1/2 ± sqrt(3)i/2.
Seyed Ali Fathima S a math expert with nearly 5 years of experience as a math teacher. From an engineer to a math teacher, shows her passion for math and teaching. She is a calculator queen, who loves tables and she turns tables to puzzles and songs.
: She has songs for each table which helps her to remember the tables






