Find every cube root of any complex input. See modulus, arguments, and rectangular form conversions. Download tables, verify steps, and practice with sample values.
| Input z | Modulus | Principal Argument | Cube Root Modulus | Cube Roots |
|---|---|---|---|---|
| 1 + 0i | 1 | 0° | 1 | 1 + 0i, -0.5000 + 0.8660i, -0.5000 - 0.8660i |
| 8 + 0i | 8 | 0° | 2 | 2 + 0i, -1.0000 + 1.7321i, -1.0000 - 1.7321i |
| 0 + 8i | 8 | 90° | 2 | 1.7321 + 1.0000i, -1.7321 + 1.0000i, 0.0000 - 2.0000i |
| -8 + 0i | 8 | 180° | 2 | 1.0000 + 1.7321i, -2.0000 + 0.0000i, 1.0000 - 1.7321i |
For a complex number z = a + bi, first convert it to polar form.
Modulus: r = √(a2 + b2)
Argument: θ = atan2(b, a)
Cube root modulus: ρ = 3√r
Cube roots:
wk = ρ [cos((θ + 2πk) / 3) + i sin((θ + 2πk) / 3)], where k = 0, 1, 2
Rectangular coordinates:
xk = ρ cos((θ + 2πk) / 3)
yk = ρ sin((θ + 2πk) / 3)
This cube roots of complex numbers calculator helps you find all three cube roots of a complex value quickly. It is useful for algebra, trigonometry, engineering math, and signal analysis. Many students can convert a complex number into polar form, yet they still struggle when several roots appear. This page solves that problem with clear output and structured steps.
The tool starts from the rectangular form z = a + bi. It computes the modulus and the principal argument. Then it applies the cube root relationship from polar form. The result section lists every cube root, not only the principal one. It also shows each root in rectangular form. That makes the output easy to verify by cubing the answer again.
Complex roots are easiest to understand through modulus and angle. When you take a cube root, the modulus becomes the ordinary cube root of the original modulus. The angle is divided by three. Extra solutions appear because angles that differ by full turns still describe the same input number. This is why the calculator uses three angle values and returns three valid roots.
You can use this calculator while solving polynomial equations, studying De Moivre style identities, or checking homework answers. It is also useful in control systems, electrical topics, and advanced problem sets where polar and rectangular forms appear together. The export options make it easier to save classroom examples, worksheets, and revision notes.
The included example data table gives you fast reference points. The formula section explains the exact expressions used. The FAQ section answers common questions about arguments, repeated roots, and angle units. Together, these sections make the page more than a simple calculator. It becomes a compact learning resource for anyone working with complex number roots.
Every nonzero complex number has exactly three cube roots. They are equally spaced around the complex plane by 120 degrees, or 2π/3 radians.
Polar form makes root extraction simple. The modulus is rooted directly, and the argument is divided by three. That is the standard and most reliable method.
Yes. The calculator accepts positive, negative, and decimal values for both parts. It uses atan2, so the argument is placed in the correct quadrant.
The modulus is zero, and every cube root collapses to zero. In that special case, the argument is not defined, so the page marks the angle as not applicable.
No. The calculator also shows modulus and angle information. That means you can interpret the roots in polar reasoning and still read the final values in rectangular form.
Choose degrees for classroom readability and radians for advanced mathematics or analysis. The root values stay the same. Only the displayed angle unit changes.
That happens because of floating point rounding. Values that should be zero may appear as tiny decimals during computation. The formatter reduces that effect.
Yes. Use the CSV button for spreadsheet style output and the PDF button for a saved summary. Both options work from the displayed result table.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.