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Nth Root Calculator

Compute the nth root (ⁿ√x), invert to a power, or solve for the root index, with exact and decimal forms and step-by-step simplification.

Nth root

Updates as you type
Mode
What do you want to solve for? ?
Quick values (click to fill)
Common x
Common n
Inputs
Radicand (x) ?
−1k01k5k10k
Root index (n) ? even
24681012
Display (optional)
Decimal precision ?

Formula

= x1/n
Nth root: n√x = x1/n
Simplification: n√(aⁿ × b) = a · n√b
Even root: for negative x, n√x is imaginary when n is even.
Odd root: n√(−x) = −n√x when n is odd (real result).
Product rule: n√(a·b) = n√a · n√b  (a, b ≥ 0)
Reciprocal root: x1/−n = 1 / x1/n
Find n: if yⁿ = x, then n = log(x) / log(y).
x
Radicand — the number under the radical sign.
n
Root index. 2 = square root, 3 = cube root, 4 = 4th root, etc.
x1/n
Equivalent exponential form. Often easier in algebra.
Parity
Whether n is even or odd — determines how negative x behaves.
Worked example — your numbers
  1. Radicand:
  2. Root index: ()
  3. Setup:
  4. Pull out the power:
  5. Exact:
  6. Decimal:

As n grows, n√x approaches 1 for any positive x — the bigger the root, the smaller the effect. Negative radicands with even n produce pure imaginary results; with odd n they stay real and flip sign.