diff --git a/calculator.html b/calculator.html
index bf11ac3..8694920 100644
--- a/calculator.html
+++ b/calculator.html
@@ -2,8 +2,12 @@
 <title>Calculator</title><meta charset="utf-8">
 <script type="text/javascript">
 function cube() {
-var num = document.getElementById("n1");
-num.value = Math.pow(num.value, 3);
+	var num = document.getElementById("n1");
+	num.value = Math.pow(num.value, 3);
+}
+function sin() {
+	var num = document.getElementById("n1");
+	num.value = Math.sin(num.value);
 }
 </script>
 </head>
@@ -12,5 +16,6 @@ num.value = Math.pow(num.value, 3);
 Number:
 <input type="text" id="n1"><p>
 <button onclick="cube()"> x^3 </button>
+<button onclick="sin()"> sin(x) </button>
 </body>
 </html>