JavaScript: Compute the exponent of a number

JavaScript Function: Exercise-5 with Solution

Exponentiation

Write a JavaScript program to compute the exponent of a number.

Note: The exponent of a number says how many times the base number is used as a factor.
8² = 8 x 8 = 64. Here 8 is the base and 2 is the exponent.

Visual Presentation:

Sample Solution-1:

JavaScript Code:

// Recursive JavaScript function to calculate the exponent (a^n).
var exponent = function(a, n) {
 // Base case: if n is 0, return 1.
 if (n === 0) {
 return 1;
 } else {
 // Recursive case: a^n = a * a^(n-1).
 return a * exponent(a, n - 1);
 }
};
// Example usage: Calculate and print the exponentiation of 4^2.
console.log(exponent(4, 2)); 

Output:

16

Flowchart:

Live Demo:

See the Pen javascript-recursion-function-exercise-5 by w3resource (@w3resource) on CodePen.

Sample Solution-2:

JavaScript Code:

// Recursive JavaScript function to calculate the exponent (a^n).
function exponent(base, power) {
 if (power === 0) {
 return 1;
 } else if (power % 2 === 0) {
 // If the power is even, use the formula (a^(n/2))^2.
 let temp = exponent(base, power / 2);
 return temp * temp;
 } else {
 // If the power is odd, use the formula a * a^(n-1).
 return base * exponent(base, power - 1);
 }
}
// Example usage: Calculate and print the exponentiation of 4^2.
console.log(exponent(4, 2));

Output:

16

Flowchart:

For more Practice: Solve these Related Problems:

• Write a JavaScript function that calculates b^n using recursion with the exponentiation by squaring method.
• Write a JavaScript function that computes the exponent of a number iteratively without using Math.pow.
• Write a JavaScript function that recursively computes the power of a number and validates the input types.
• Write a JavaScript function that calculates b^n using recursion and handles negative exponents by computing reciprocals.

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