Calculator
Example Data Table
| Complex number | Modulus | Argument | Polar form |
|---|---|---|---|
| 3 + 4i | 5 | 53.1301° | 5 ∠ 53.1301° |
| -2 + 2i | 2.8284 | 135° | 2.8284 ∠ 135° |
| 0 - 6i | 6 | 270° | 6 ∠ 270° |
| -5 - 12i | 13 | 247.3801° | 13 ∠ 247.3801° |
| 1 + 1.7321i | 2 | 60° | 2 ∠ 60° |
Formula Used
For a complex number z = a + bi, the modulus is:
r = √(a² + b²)
The argument is:
θ = atan2(b, a)
The polar, trigonometric, and exponential forms are:
z = r ∠ θ
z = r(cos θ + i sin θ)
z = reiθ
To convert polar form back to rectangular form:
a = r cos θ
b = r sin θ
For powers:
zⁿ = rⁿ[cos(nθ) + i sin(nθ)]
For nth roots:
zk = r1/n[cos((θ + 2πk)/n) + i sin((θ + 2πk)/n)]
How to Use This Calculator
- Select rectangular mode when you know a and b.
- Select polar mode when you know radius and angle.
- Choose degrees or radians for angle input.
- Select the angle display range you prefer.
- Enter decimal places for rounded answers.
- Add a power value if you need z raised to n.
- Enter the root count for nth root values.
- Press Calculate to view results above the form.
- Use CSV or PDF export for saving the result.
Understanding Polar Form
Basic Idea
A complex number can be written as a plus bi. That form is clear for addition. Polar form explains the same value with distance and angle. The distance is the modulus. The angle is the argument. Together, they show position from the origin.
Why This Calculator Helps
Manual conversion is simple, but mistakes happen often. Signs can change the quadrant. Radian and degree units can also confuse learners. This calculator keeps those choices visible. It shows each main result with rounded values. It also builds trigonometric and exponential forms.
Useful Study Details
The modulus tells how far the point sits from zero. The argument tells the direction of the point. A positive imaginary value points upward. A negative imaginary value points downward. The calculator uses atan2, so quadrants are handled correctly. It can normalize angles to common ranges.
Powers and Roots
Polar form becomes powerful with De Moivre calculations. Powers multiply the angle and raise the modulus. Roots split the angle into equal branches. This is useful in algebra, signals, control systems, and AC circuit work. The tool lists the first roots when a root count is selected.
Export and Review
The result can be downloaded as a CSV file. A simple PDF report can also be saved. These exports help with homework checks and project records. The example table gives sample inputs. You can compare your own results against them.
Practical Tips
Use more decimals when precision matters. Use fewer decimals for classroom answers. Keep the imaginary sign correct. Enter zero carefully because the angle at the origin is undefined. When comparing answers, check whether your source uses degrees or radians. Both forms may represent the same complex number.
Common Input Choices
The rectangular mode starts from real and imaginary parts. The polar mode starts from radius and angle. A negative radius is adjusted internally. The calculator reports a standard positive modulus. This keeps results consistent across examples and textbooks. It also protects many downstream calculations well.
Interpreting Results
Rectangular form is best when adding or subtracting complex numbers. Polar form is often best when multiplying, dividing, raising powers, or taking roots. The reciprocal result shows the inverse complex value. The conjugate changes only the imaginary sign. These related values help verify the calculation from more than one view. Always note the selected angle mode before copying a result.
FAQs
What is polar form of a complex number?
Polar form writes a complex number using a modulus and angle. It shows distance from the origin and direction from the positive real axis.
What does the modulus mean?
The modulus is the distance of the complex point from zero. For a + bi, it equals the square root of a squared plus b squared.
What does the argument mean?
The argument is the angle made with the positive real axis. This calculator uses atan2 to keep the correct quadrant.
Can this calculator convert polar to rectangular form?
Yes. Select polar mode. Then enter radius and angle. The tool returns real and imaginary parts using cosine and sine.
Why is the angle undefined for zero?
The complex number zero has no direction from the origin. Its distance is zero, so any angle would point to the same location.
What is exponential complex form?
Exponential form writes the number as re raised to iθ. It is compact and useful in engineering, waves, and advanced algebra.
How are powers calculated?
Powers use De Moivre’s rule. The modulus is raised to n, and the angle is multiplied by n.
How many roots can I calculate?
This file allows up to twelve roots. That keeps the result readable while still covering most study and review needs.