find the Nth root
of a number
[ Math.pow ]

Find the Nth root of a number

Write a function that takes two numbers, the first number representing the root and the second representing the number that we want to find the root of.

root → number to calculate

number → number whose root is to be found

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

Root of a number

The root of a number n is another number, which when multiplied by itself a given number of times, equals n

For example, the third root of 64 is 4, because if you multiply three fours together you get 64 4 × 4 × 4 = 64

This would be written as 3√ 64 = 4

This would be spoken as "the third root of 64 is 4" or "the cube root of 64 is 4".

The second root is usually called the square root

The third root of a number is usually called the cube root

After that, they are called the nth root, for example the 4th root, 5th root, 6th root, etc.

If root is missing, it is assumed to be 2, the square root.

Example ...

Enter root to find and the number ...

2√81 returns → 9 9 × 9 = 81

3√27 returns → 3 3 × 3 × 3 = 27

4√16 returns → 2 2 × 2 × 2 × 2 = 16

Numbers are used to represent both integer and floating-point values.

Numbers are most commonly expressed in literal forms like 255 or 3.14159 ↴

let num1 = 5; → number

let num2 = 2.5; → number

let num3 = num1 + num2;

console.log(num3); returns ↴

7.5 → number

Find the Nth root of a number using the Math.pow() method.

Math.pow() static method returns the value of a base raised to a power.

Math.pow(x, y) = xy

Math.pow(2, 2) 22 2 × 2 → 4

Math.pow(2, 3) 23 2 × 2 × 2 → 8

Math.pow(3, 3) 33 3 × 3 × 3 → 27

Math.pow(3, 4) 34 3 × 3 × 3 × 3 → 81

Math.pow() is equivalent to the exponent operator ** except Math.pow() only accepts numbers.

Initialize a variable to hold the root value.

const num1 = 2; → user input

Initialize a variable to hold the number whose root is to be found.

const num2 = 81; → user input

Define a function findRoot to find the root of a number.

function findRoot(str) {}

The function takes two numbers as input num1, num2 representing the root and the number whose root is to be found.

num1 → root

num2 → number

A negative root (exponent) results in the reciprocal of the base raised to the positive exponent.

A negative base with a fractional root (exponent) can lead to NaN in JavaScript, as it does not handle complex numbers.

Check if the root is a negative number.

if (root <= 0) {}

If true, throw an error.

throw new Error("The root must be a positive number.")

If root is positive number, calculate and return the root using Math.pow

return Math.pow(num, 1 / root) Returns the root of the number

Call the function with ↴

findRoot(num1, num2);

Find the Nth root of a number.

2√81 → find square root of 81

const num1 = 2;

const num2 = 81;

function findRoot(root, num) {

if (root <= 0) {

throw new Error("The root must be a positive number.");

}

return Math.pow(num, 1 / root);

}

call function

findRoot(num1, num2); returns ↴

9

Alternative to find the square root of a number using built-in Math.sqrt() method ↴

Math.sqrt(81); returns ↴

9

Find the Nth root of a number

root √
number
to decimal places
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