Algebra studio

Root Calculator

World-class square, cube, and general n-th root calculator inspired by calculator.net, but redesigned with modern UX, triangle-style radical diagram, and full estimation walkthroughs. Enter any radicand and instantly see the real-valued root with equation context and precision control.

Square root

√a Calculator

√a = ?

Cube root

∛a Calculator

∛a = ?

General n-th root

n√a Calculator

Notes: Even roots of negative numbers are not real. This tool returns real-number roots only. Increase precision for more decimal places.

Diagram

Radical triangle

A stylized triangle diagram illustrates the root operation: the radical bar behaves like a hypotenuse hovering above the base. Use it as a visual mnemonic while estimating.

n√anth root geometry

In mathematics, the general root

In mathematics, the general root, or the nth root of a number a is another number b that when multiplied by itself n times, equals a. In equation format:

n√a = b

bⁿ = a

Estimating a Root

Some common roots include the square root, where n = 2, and the cubed root, where n = 3. Calculating square roots and nth roots is fairly intensive. It requires estimation and trial and error. There exist more precise and efficient ways to calculate square roots, but below is a method that does not require a significant understanding of more complicated math concepts. To calculate √a:

1. Estimate a number b.

2. Divide a by b. If the number c returned is precise to the desired decimal place, stop.

3. Average b and c and use the result as a new guess.

4. Repeat step two.

Estimating an nth Root

Calculating nth roots can be done using a similar method, with modifications to deal with n. While computing square roots entirely by hand is tedious, estimating higher nth roots, even if using a calculator for intermediary steps, is significantly more tedious. For those with an understanding of series, refer here for a more mathematical algorithm for calculating nth roots. For a simpler, but less efficient method, continue to the following steps and example. To calculate n√a:

1. Estimate a number b.

2. Divide a by bⁿ⁻¹. If the number c returned is precise to the desired decimal place, stop.

3. Average: [b × (n − 1) + c] / n.

4. Repeat step two.

Estimating √27

EX: Find √27 to 3 decimal places

Guess: 5.125

27 ÷ 5.125 = 5.268

(5.125 + 5.268) / 2 = 5.197

27 ÷ 5.197 = 5.195

(5.195 + 5.197) / 2 = 5.196

27 ÷ 5.196 = 5.196

Estimating ⁸√15

EX: Find ⁸√15 to 3 decimal places

Guess: 1.432

15 ÷ 1.432⁷ = 1.405

(1.432 × 7 + 1.405) / 8 = 1.388

15 ÷ 1.388⁷ = 1.403

(1.403 × 7 + 1.388) / 8 = 1.402

Further computation would still round to 1.403 at 3 decimal places.