Finding Nth Root Of A Number Using JavaScript

With below code, we can find the nth root of a number by making use of Math.pow() function in javascript,

 Number :
<input type="text" id="txtnumber" /><br />
<br />
Root :
<input type="text" id="txtroot" /><br />
<br />
<button onclick="getrootval()">
        Find Root</button>
<script>
        function getrootval() {
            var num = document.getElementById("txtnumber").value;
            var root = document.getElementById("txtroot").value;
            var str = root + "th root of " + num + " is ";
            if (parseFloat(root) == 1.0) {
                str = "First Root of " + num + " is ";
            }
            else if (parseFloat(root) == 2.0) {
                str = "Square Root of " + num + " is ";
            }
            else if (parseFloat(root) == 3.0) {
                str = "Cube Root of " + num + " is ";
            }
            num = Math.pow(num, (1 / parseFloat(root)));
            alert(str + num);
        }
</script>

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