Update index.html

Fix

Author: Gmac4247

index.html

@@ -5083,7 +5083,6 @@ <h3 itemprop="name" style="margin:7px">Calculate the Volume of a Frustum Cone</h
           </mfrac>
         </mrow>
       </mfrac>
-      <mo>)</mo>
       <mo>-</mo>
       <msup>
 			<msub>