Root Calculator
x1/n = Result
Example:
If x = 16 and n = 2 (Square Root):
161/2 = 4
What Is a Root in Mathematics?
In math, a root is a number that, when multiplied by itself several times, equals a given value. This is called the nth root. For example:
n√a = b
bⁿ = a
If b multiplied by itself n times equals a, then b is the nth root of a.
Common Types of Roots
Square Root (n = 2)
Cube Root (n = 3)
These are frequently used in algebra, geometry, and everyday calculations.
How to Estimate a Square Root (√a)
Step-by-Step Method
You can estimate a square root manually using a basic approach. No advanced math is needed—just follow these steps:
Make a guess (b)
Divide a by b to get c
Find the average: (b + c) / 2
Use this new value as the next guess and repeat step 2 until it’s accurate
Example: Estimate √27 to 3 Decimal Places
Start with a guess: 5.125
27 ÷ 5.125 = 5.268
Average: (5.125 + 5.268) / 2 = 5.197
27 ÷ 5.197 = 5.195
Average: (5.195 + 5.197) / 2 = 5.196
27 ÷ 5.196 = 5.196
Final Answer: √27 ≈ 5.196
How to Estimate an Nth Root (n√a)
Steps to Manually Find an Nth Root
Estimating higher roots is similar but needs a slight adjustment in the formula:
Guess a starting number (b)
Divide a by bⁿ⁻¹ to get c
Update your guess using: [(b × (n – 1)) + c] / n
Repeat the process until the value is accurate
Example: Estimate 8th Root of 15 (8√15) to 3 Decimal Places
First guess: 1.432
15 ÷ (1.432⁷) = 1.405
Average: (1.432 × 7 + 1.405) / 8 = 1.388
15 ÷ (1.388⁷) = 1.403
Average: (1.403 × 7 + 1.388) / 8 = 1.402
Final Answer: 8√15 ≈ 1.403