CubeRoot

CubeRoot[x]

gives the real-valued cube root of x.

Details

  • CubeRoot[x] returns the real-valued cube root for real-valued x.
  • For symbolic x in CubeRoot[x], x is assumed to be real valued.
  • CubeRoot can be evaluated to arbitrary numerical precision.
  • CubeRoot automatically threads over lists.
  • In StandardForm, CubeRoot[x] formats as .
  • can be entered as cbrt.
  • ∛z can also be used for input. The character is entered as cbrti or \[CubeRoot].

Examples

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Basic Examples  (5)

CubeRoot gives a real root:

Plot over a subset of the reals:

Enter using cbrt:

Note that this is not the same as , which is Power[x,1/3]:

Compare the real and imaginary parts of and over the reals:

Series expansion:

Scope  (34)

Numerical Evaluation  (4)

Evaluate numerically:

Evaluate to high precision:

The precision of the output tracks the precision of the input:

Evaluate efficiently at high precision:

CubeRoot threads elementwise over lists and matrices:

Specific Values  (4)

Values of CubeRoot at fixed points:

Values at zero:

Values at infinity:

Find a value of for which the using Solve:

Substitute in the result:

Visualize the result:

Visualization  (3)

Plot the CubeRoot function:

Visualize the absolute value and argument (sign) of :

The function has the same absolute value but a different argument for :

Polar plot with :

Function Properties  (9)

CubeRoot is defined on the real numbers:

The range of CubeRoot is all real numbers:

Enter a character as \[CubeRoot], followed by a number:

is not an analytic function:

Neither is it meromorphic:

is non-decreasing:

is injective:

And surjective:

is neither non-negative nor non-positive:

is continuous on the reals but has a singularity at :

It is singular because it is not differentiable:


is neither convex nor concave:

Differentiation  (3)

First derivative with respect to x:

Higher derivatives with respect to x:

Plot the higher derivatives with respect to x:

Formula for the ^(th) derivative with respect to x:

Integration  (4)

Compute the indefinite integral using Integrate:

Verify the anti-derivative:

Definite integral:

Definite integral of CubeRoot over a symmetric interval is 0:

More integrals:

Series Expansions  (4)

Find the Taylor expansion using Series:

Plots of the first three approximations around :

General term in the series expansion using SeriesCoefficient:

The first-order Fourier series:

Taylor expansion at a generic point:

Function Identities and Simplifications  (3)

Primary definition:

Products can be combined using FullSimplify:

CubeRoot commutes with integer exponentiation:

Applications  (1)

Solve a differential equation with CubeRoot:

Properties & Relations  (5)

CubeRoot is only defined for real inputs:

CubeRoot is a bijection on the reals:

Use CubeRoot to find real cube roots:

Use Power[x,1/3] or to find the principal complex cube root:

The generating function for CubeRoot:

Find the integral of a function containing CubeRoot:

Visualize the function and the signed area between it and the axis:

Possible Issues  (1)

On the negative real axis, CubeRoot[x] is different from the principal root returned by Power[x,1/3]:

Wolfram Research (2012), CubeRoot, Wolfram Language function, https://reference.wolfram.com/language/ref/CubeRoot.html (updated 2020).

Text

Wolfram Research (2012), CubeRoot, Wolfram Language function, https://reference.wolfram.com/language/ref/CubeRoot.html (updated 2020).

CMS

Wolfram Language. 2012. "CubeRoot." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2020. https://reference.wolfram.com/language/ref/CubeRoot.html.

APA

Wolfram Language. (2012). CubeRoot. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/CubeRoot.html

BibTeX

@misc{reference.wolfram_2023_cuberoot, author="Wolfram Research", title="{CubeRoot}", year="2020", howpublished="\url{https://reference.wolfram.com/language/ref/CubeRoot.html}", note=[Accessed: 18-March-2024 ]}

BibLaTeX

@online{reference.wolfram_2023_cuberoot, organization={Wolfram Research}, title={CubeRoot}, year={2020}, url={https://reference.wolfram.com/language/ref/CubeRoot.html}, note=[Accessed: 18-March-2024 ]}