JSFiddle - React, Tailwind, and code Playground

HTML

<html>
<body>
<p>
</p>
</body>
</html>

JavaScript

function squareRoot(n){
    var avg=(a,b)=>(a+b)/2,c=5,b;
    for(let i=0;i<20;i++){
        b=n/c;
        c=avg(b,c);
    }
    return c;
}

function log(s){
		document.querySelector('p').innerHTML+=s;
}


log(squareRoot(25)+'<br>');
log(squareRoot(100)+'<br>');
log(squareRoot(15)+'<br>');