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Root Calculator

Square roots, cube roots and any nth root, simplified exactly (√27 = 3√3) with the decimal value.

Change the values and press Calculate to work out your own figures.

Square root

Enter a number.

About numberThe number to take the root of.
Result
Square root
5.19615242271
Simplified
3√3

The square root of 27 is 3√3 ≈ 5.19615242271.

Show the working
  1. √27 = 3√3 = 5.19615242271

Cube root

Enter a number (negatives allowed).

About numberThe number to take the root of.
Result
Cube root
-3.77976314968
Simplified
-3∛2

The cube root of -54 is -3∛2 ≈ -3.77976314968.

Show the working
  1. ∛-54 = -3∛2 = -3.77976314968

Any root

Enter the root n and the number.

About root (n)2 for square root, 3 for cube root, …
About numberThe number to take the root of.
Result
Root
1.40285055201
Simplified
⁸√15

The 8th root of 15 is ⁸√15 ≈ 1.40285055201.

Show the working
  1. ⁸√15 = ⁸√15 = 1.40285055201

How to use it

Enter a number. Enter a number (negatives allowed). Enter the root n and the number.

Number boxes accept whole numbers, decimals, fractions (3/4), powers (2^10), roots (sqrt(2)) and the constants pi and e. Show the working lists the steps.

Key facts

ⁿ√x = x^(1/n)

Simplifying

Pull out perfect powers: √27 = √(9 × 3) = 3√3.

Questions

What is √27?

3√3 ≈ 5.19615242271.

Can I take a cube root of a negative number?

Yes: ∛−54 = −3∛2.

Formulas

ⁿ√x = x^(1/n)

Sources

Limitations

  • Expressions up to 500 characters; matrices up to 10 × 10.
  • Big-number results up to 100,000 digits; factorials up to 10,000!.
  • Numbers in words up to 10^102 (short scale).

Formula version 0.1.0Reviewed