how to add in javascript code example

Example 1: how to add elements in javascript html

//adding 'p' tag to body

  var tag = document.createElement("p"); // <p></p>
  var text = document.createTextNode("TEST TEXT"); 
  tag.appendChild(text); // <p>TEST TEXT</p>
  var element = document.getElementsByTagName("body")[0];
  element.appendChild(tag); // <body> <p>TEST TEXT</p> </body>

Example 2: javascript function to add two numbers

<!--Add two integer numbers using JavaScript.-->
<html>
	<head>
		<title>Add two integer numbers using JavaScript.</title>
		<script type="text/javascript">
			function addTwoNumbers(textBox1, textBox2){
				var x=document.getElementById(textBox1).value;
				var y=document.getElementById(textBox2).value;
				var sum=0;
				sum=Number(x)+Number(y);
				alert("SUM is: " + sum);
			}
		</script>
	</head>
<body>
	<h1>Add two integer numbers using JavaScript.</h1>
	<b>Enter first Number: </b><br>
	<input type="text" id="textIn1"/><br>
	<b>Enter second Number: </b><br>
	<input type="text" id="textIn2"/><br><br>
	<input type="button" id="btnSum" value="Calculate SUM" onClick="addTwoNumbers('textIn1','textIn2')"/>
</body>

</html>

Example 3: adding numbers in Javscript

return a+b;

Example 4: ... in javascript

function sum(x, y, z) {
  return x + y + z;
}

const numbers = [1, 2, 3];

console.log(sum(...numbers));
// expected output: 6

console.log(sum.apply(null, numbers));
// expected output: 6

/* Spread syntax (...) allows an iterable such as an array expression or string 
to be expanded in places where zero or more arguments (for function calls) 
or elements (for array literals) are expected, or an object expression to be 
expanded in places where zero or more key-value pairs (for object literals) 
are expected. */

// ... can also be used in place of `arguments`
// For example, this function will add up all the arguments you give to it
function sum(...numbers) {
  let sum = 0;
  for (const number of numbers)
    sum += number;
  return sum;
}

console.log(sum(1, 2, 3, 4, 5));
// Expected output: 15

// They can also be used together, but the ... must be at the end
console.log(sum(4, 5, ...numbers));
// Expected output: 15

Example 5: js add

//HOW TO ADD:
var num1 = 4;
var num2 = 6;
var answer = 4 + 6; //You can do num1 + num2 here!
function add(num1, num2) {
  return num1 + num2;
};
console.log("4 + 6 is: " + add());
console.log("I hope this helped!");

Example 6: add javascript

<script src="myScript.js"></script>