Calculator Cube Root

There are 3 solutions, due to “The Fundamental Theorem of Algebra”. Your expression contains roots of complex numbers or powers to 1/n.

z₁ = cuberoot(1-27i) = 2.6169858-1.4681616i = 3.0006855 × e^{i -0.5112587} = 3.0006855 × e^{i (-0.1627387) π} Calculation steps principal root

Complex number: 1-27i
Cube root: ∛(the result of step No. 1) = ∛(1-27i) = 2.6169858-1.4681616i

The result z₁

Rectangular form (standard form):
z = 2.6169858-1.4681616i

Angle notation (phasor, modulus and argument):
z = 3.0006855 ∠ -29°17'35″

Polar form:
z = 3.0006855 × (cos (-29°17'35″) + i sin (-29°17'35″))

Exponential form:
z = 3.0006855 × e^{i -0.5112587} = 3.0006855 × e^{i (-0.1627387) π}

Polar coordinates:
r = |z| = 3.0006855 ... magnitude (modulus, absolute value)
θ = arg z = -0.5112587 rad = -29.29297° = -29°17'35″ = -0.1627387π rad ... angle (argument or phase)

Cartesian coordinates:
Cartesian form of imaginary number: z = 2.6169858-1.4681616i
Real part: x = Re z = 2.617
Imaginary part: y = Im z = -1.46816164

z₂ = cuberoot(1-27i) = -0.0370276+3.000457i = 3.0006855 × e^{i 1.5831364} = 3.0006855 × e^{i 0.503928 π} Calculation steps

Complex number: 1-27i
Cube root: ∛(the result of step No. 1) = ∛(1-27i) = -0.0370276+3.000457i

The result z₂

Rectangular form (standard form):
z = -0.0370276+3.000457i

Angle notation (phasor, modulus and argument):
z = 3.0006855 ∠ 90°42'25″

Polar form:
z = 3.0006855 × (cos 90°42'25″ + i sin 90°42'25″)

Exponential form:
z = 3.0006855 × e^{i 1.5831364} = 3.0006855 × e^{i 0.503928 π}

Polar coordinates:
r = |z| = 3.0006855 ... magnitude (modulus, absolute value)
θ = arg z = 1.5831364 rad = 90.70703° = 90°42'25″ = 0.503928π rad ... angle (argument or phase)

Cartesian coordinates:
Cartesian form of imaginary number: z = -0.0370276+3.000457i
Real part: x = Re z = -0.037
Imaginary part: y = Im z = 3.00045702

z₃ = cuberoot(1-27i) = -2.5799582-1.5322954i = 3.0006855 × e^{i -2.6056538} = 3.0006855 × e^{i (-0.8294054) π} Calculation steps

Complex number: 1-27i
Cube root: ∛(the result of step No. 1) = ∛(1-27i) = -2.5799582-1.5322954i

The result z₃

Rectangular form (standard form):
z = -2.5799582-1.5322954i

Angle notation (phasor, modulus and argument):
z = 3.0006855 ∠ -149°17'35″

Polar form:
z = 3.0006855 × (cos (-149°17'35″) + i sin (-149°17'35″))

Exponential form:
z = 3.0006855 × e^{i -2.6056538} = 3.0006855 × e^{i (-0.8294054) π}

Polar coordinates:
r = |z| = 3.0006855 ... magnitude (modulus, absolute value)
θ = arg z = -2.6056538 rad = -149.29297° = -149°17'35″ = -0.8294054π rad ... angle (argument or phase)

Cartesian coordinates:
Cartesian form of imaginary number: z = -2.5799582-1.5322954i
Real part: x = Re z = -2.58
Imaginary part: y = Im z = -1.53229538

This calculator supports all operations with complex numbers and evaluates expressions in the complex number system. You can use i (mathematics) or j (electrical engineering) as the imaginary unit, both satisfying the fundamental property i² = −1 or j² = −1.

Additionally, the calculator can convert complex numbers into:

Angle notation (phasor notation)
Exponential form
Polar coordinates (magnitude and angle)

Example input: 5*(1+i)(-2-5i)^2

Complex numbers in the angle notation or phasor (polar coordinates r, θ) may be written as rLθ where r is magnitude/amplitude/radius, and θ is the angle (phase) in degrees, for example, 5L65 which is the same as 5*cis(65°).
Example of multiplication of two imaginary numbers in the angle/polar/phasor notation: 10L45 * 3L90.

For use in education (for example, calculations of alternating currents at high school), you need a quick and precise complex number calculator.

Basic operations with complex numbers

We hope that working with complex numbers is quite easy because you can work with the imaginary unit i as a variable and use the definition i² = -1 to simplify complex expressions. Many operations are the same as operations with two-dimensional vectors.

Addition

It is very simple: add up the real parts (without i) and add up the imaginary parts (with i):
This is equivalent to using the rule: (a+bi)+(c+di) = (a+c) + (b+d)i

(1+i) + (6-5i) = 7-4i
12 + 6-5i = 18-5i
(10-5i) + (-5+5i) = 5

Subtraction

Again it is very simple: subtract the real parts and subtract the imaginary parts (with i):
This is equivalent to using the rule: (a+bi)-(c+di) = (a-c) + (b-d)i

(1+i) - (3-5i) = -2+6i
-1/2 - (6-5i) = -6.5+5i
(10-5i) - (-5+5i) = 15-10i

Multiplication

To multiply two complex numbers, use the distributive law, expand the binomials, and apply i² = -1.
This is equivalent to using the rule: (a+bi)(c+di) = (ac-bd) + (ad+bc)i

(1+i) (3+5i) = 1*3+1*5i+i*3+i*5i = 3+5i+3i-5 = -2+8i
-1/2 * (6-5i) = -3+2.5i
(10-5i) * (-5+5i) = -25+75i

Division

The division of two complex numbers can be accomplished by multiplying the numerator and denominator by the denominator's complex conjugate. This approach eliminates the imaginary unit i from the denominator. If the denominator is c+di, to make it without i (or make it real), multiply with conjugate c-di:

(c+di)(c-di) = c²+d²

\frac{a + b i}{c + d i} = \frac{( a + b i ) ( c - d i )}{( c + d i ) ( c - d i )} = \frac{a c + b d + i ( b c - a d )}{c ^{2} + d ^{2}} = \frac{a c + b d}{c ^{2} + d ^{2}} + \frac{b c - a d}{c ^{2} + d ^{2}} i

(10-5i) / (1+i) = 2.5-7.5i
-3 / (2-i) = -1.2-0.6i
6i / (4+3i) = 0.72+0.96i

Absolute value or modulus

The absolute value or modulus is the distance of the image of a complex number from the origin in the plane. The calculator uses the Pythagorean theorem to find this distance. Very simple, see examples: |3+4i| = 5
|1-i| = 1.4142136
|6i| = 6
abs(2+5i) = 5.3851648

Square root

The square root of a complex number (a+bi) is z, if z² = (a+bi). Here ends simplicity. Because of the fundamental theorem of algebra, you will always have two different square roots for a given number. If you want to find out the possible values, the easiest way is to use De Moivre's formula. Our calculator can handle this because the square root is not a well-defined function on complex numbers. We calculate all complex roots from any number - even in expressions:

sqrt(9i) = 2.1213203+2.1213203i
sqrt(10-6i) = 3.2910412-0.9115656i
pow(-32,1/5)/5 = -0.4
pow(1+2i,1/3)*sqrt(4) = 2.439233+0.9434225i
pow(-5i,1/8)*pow(8,1/3) = 2.3986959-0.4771303i

Square, power, complex exponentiation

Our calculator can raise any complex number to an integer (positive, negative), real, or even complex number. In other words, we calculate 'complex number to a complex power' or 'complex number raised to a power'...
Famous example:

i^{i} = e^{- π / 2}

i^2 = -1
i^61 = i
(6-2i)^6 = -22528-59904i
(6-i)^4.5 = 2486.1377428-2284.5557378i
(6-5i)^(-3+32i) = 2929449.0399425-9022199.5826224i
i^i = 0.2078795764
pow(1+i,3) = -2+2i

Functions

sqrt: Square Root of a value or expression.
sin: the sine of a value or expression. Autodetect radians/degrees.
cos: the cosine of a value or expression. Autodetect radians/degrees.
tan: The tangent of a value or expression. Autodetect radians/degrees.
exp: e (the Euler's number) raised to the power of a value or expression
pow: Raise one complex number to another integer/real/complex power
ln: The natural logarithm of a value or expression
log: The base-10 logarithm of a value or expression
abs or |1+i|: The absolute value of a value or expression
phase: Phase (angle) of a complex number
cis: a lesser-known notation: cis(x) = cos(x)+ i sin(x); example: cis (pi/2) + 3 = 3+i
conj: the conjugate of a complex number - example: conj(4i+5) = 5-4i