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Root Calculator

Work out square, cube or nth roots. Get an exact form or a decimal; simplify where possible.

Square Root Calculator

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Example: √16 = 4

Cube Root Calculator

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Example: ∛27 = 3

nth Root Calculator

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Example: ⁴√16 = 2

Roots in short

A root is the reverse of a power: if yⁿ = x, then the nth root of x is y. Useful when you know an area or volume and want a length.

  • Square root: √x = y, if y² = x.
  • Cube root: ∛x = y, if y³ = x.
  • nth root: √[n]x = y, if yⁿ = x.

Useful Properties

  • √(a × b) = √a × √b (if a, b ≥ 0).
  • √(a²) = |a|.
  • √[n](aⁿ) = a, if n is even and a ≥ 0.
  • Roots can be written as fractional powers.

Calculation methods

Simplify by writing the number as a product of square factors. E.g. √18 = √(9×2) = 3√2.

For nth roots, use known perfect nth powers or a decimal approximation.

Examples

√18 = 3√2.

∛27 = 3.

⁵√32 = 2.

√50 = √(25×2) = 5√2.

Tips

  • Negative input? For an even root (e.g. square root) there is no real number result.
  • How to simplify? Split the number into square factors (4, 9, 16, …).
  • For simplification and properties explained in plain language, use the main solver.