JSFiddle - React, Tailwind, and code Playground

HTML

<div id="result1">100000</div>
<div id="result2">10</div>
<div id="rate">13.4</div>
<div id="month">
</div>

JavaScript

function platezh() {
    var stavka = document.getElementById('rate').innerText;
    var summa = document.getElementById('result1').innerText;
    var srok = document.getElementById('result2').innerText;
    var platezh = summa*stavka*(pow(1+stavka,srok))/(pow(1+stavka,srok))-1;
    document.getElementById('month').innerHTML = platezh;
}