7. Arithmetic

Arithmetic operations are the foundation of many programming tasks. They allow you to perform calculations, manipulate numbers, and build more complex logic in your programs.

7.1. Operators

JavaScript provides several operators for performing arithmetic:

Addition

let sum = 5 + 3;
console.log(sum); // Prints: 8

Subtraction

let difference = 10 - 4;
console.log(difference); // Prints: 6

Multiplication

let product = 6 * 7;
console.log(product); // Prints: 42

Division

let quotient = 20 / 5;
console.log(quotient); // Prints: 4

Modulus

Finds the remainder when one number is divided by another.

let remainder = 10 % 3;
console.log(remainder); // Prints: 1

Power (Exponent)

The first number is the base and the second number is the power. For example you would read 4**2 as ‘4 to the power of 2’, i.e., which is 16.

let exponent = 4**2;
console.log(exponent); // Prints: 16

7.2. Order of Operations (PEMDAS)

JavaScript follows the order of operations, also known as PEMDAS:

Parentheses Exponents Multiplication and Division Addition and Subtraction Example:

let result = 5 + 2 * 3; console.log(result); // Prints: 11 (Multiplication happens before addition)

let resultWithParentheses = (5 + 2) * 3; console.log(resultWithParentheses); // Prints: 21 (Parentheses are evaluated first)

7.3. Special Cases

Dividing by Zero In JavaScript, dividing by zero results in Infinity or -Infinity for positive and negative numbers, respectively. Example: console.log(5 / 0); // Prints: Infinity console.log(-5 / 0); // Prints: -Infinity Not a Number (NaN) If an arithmetic operation involves invalid inputs (like dividing a string by a number), JavaScript returns NaN (Not a Number). Example: console.log(“hello” / 2); // Prints: NaN