Complex Number to Trigonometric Form Calculator

Convert complex numbers from rectangular form (a + bi) to trigonometric form r[cos(φ) + isin(φ)]

Convert Rectangular to Trigonometric Form

Horizontal component on complex plane

Vertical component on complex plane

Current Rectangular Form

z = 0

Trigonometric Form Results

Magnitude |z|
0.0000
Argument φ
0.0° = 0.0000 rad
Trigonometric Form (Degrees)
z = 0
Trigonometric Form (Radians)
z = 0

Conversion formulas:

• Magnitude: |z| = (a² + b²) = (0² + (0)²) = 0.0000

• Argument: φ = atan2(b, a) = atan2(0, 0) = 0.0000 rad

• Trigonometric form: z = |z| × [cos(φ) + i × sin(φ)]

Common Example Conversions

1 + 0i
[cos(0°) + i × sin(0°)]
0 + i
[cos(90°) + i × sin(90°)]
1 + i
1.41 × [cos(45°) + i × sin(45°)]
-1 + i
1.41 × [cos(135°) + i × sin(135°)]
-1 - i
1.41 × [cos(-135°) + i × sin(-135°)]
1 - i
1.41 × [cos(-45°) + i × sin(-45°)]
3 + 4i
5 × [cos(53°) + i × sin(53°)]
5 + 0i
5 × [cos(0°) + i × sin(0°)]

Complex Number Forms

Rectangular Form

z = a + bi

Where a = real part, b = imaginary part

Trigonometric Form

z = r[cos(φ) + isin(φ)]

Where r = magnitude, φ = argument

Polar (Exponential) Form

z = r × e^(iφ)

Compact exponential notation

Conversion Formulas

Rectangular → Trigonometric

r = (a² + b²)

φ = atan2(b, a)

z = r[cos(φ) + isin(φ)]

Trigonometric → Rectangular

a = r × cos(φ)

b = r × sin(φ)

z = a + bi

Common Angles

cos(0°) = 1, sin(0°) = 0
30°cos(30°) = 3/2, sin(30°) = 1/2
45°cos(45°) = 2/2, sin(45°) = 2/2
60°cos(60°) = 1/2, sin(60°) = 3/2
90°cos(90°) = 0, sin(90°) = 1

Quick Tips

Trigonometric form is useful for multiplication and division

Magnitude r is always non-negative

Argument φ is typically given in [-π, π]

Use atan2(b, a) for correct quadrant determination

Understanding Trigonometric Form of Complex Numbers

What is Trigonometric Form?

The trigonometric form represents a complex number as z = r[cos(φ) + isin(φ)], where 'r' is the magnitude (distance from origin) and 'φ' is the argument (angle from positive real axis).

Why Use Trigonometric Form?

  • Multiplication and division become easier
  • Powers and roots are simplified using De Moivre's theorem
  • Clear geometric interpretation on complex plane
  • Connection between algebra and trigonometry

Conversion Process

From: z = a + bi

To: z = r[cos(φ) + isin(φ)]

Step 1: Calculate magnitude using r = (a² + b²)

Step 2: Calculate argument using φ = atan2(b, a)

Step 3: Write trigonometric form

Note: atan2(b, a) automatically handles quadrant determination correctly!

Operations with Trigonometric Form

Multiplication

z₁ × z₂ = r₁r₂[cos(φ₁ + φ₂) + isin(φ₁ + φ₂)]

Multiply magnitudes, add arguments

Division

z₁ ÷ z₂ = (r₁/r₂)[cos(φ₁ - φ₂) + isin(φ₁ - φ₂)]

Divide magnitudes, subtract arguments

Powers (De Moivre's Theorem)

z^n = r^n[cos(nφ) + isin(nφ)]

Raise magnitude to power n, multiply argument by n

nth Roots

z^(1/n) = r^(1/n)[cos((φ + 2kπ)/n) + isin((φ + 2kπ)/n)]

Where k = 0, 1, 2, ..., n-1