Update index.html

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Author: Gmac4247

index.html

@@ -524,7 +524,6 @@ <h2 style="font-size:100%">This system doesn't require advanced calculus or imag
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 <h3 style="margin:7px">Key Points</h3>
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@@ -571,7 +570,7 @@ <h4 style="margin:7px">Algebraic Manipulation</h4>
 <p style="margin:12px"><strong>Simplifying equations to ensure consistency and precision.
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@@ -1148,7 +1147,6 @@ <h3 style="margin:7px">Volume of a cube</h3>
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@@ -1157,7 +1155,6 @@ <h3 style="margin:7px">Volume of a cube</h3>
 <h2 style="margin:7px">Geometry</h2>
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 <h3 style="margin:7px">Trigonometry</h3>
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@@ -2084,7 +2081,6 @@ <h3 style="margin:7px">Area of a regular polygon</h3>
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@@ -3497,7 +3493,7 @@ <h3 style="margin:7px">The volume of a sphere is defined by comparing it to a cu
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+<section id="sphere_surface" style="border: 2px solid red; 
             padding: 10px" id="sphere-surface">
   <p style="margin:6px">Advertisement</p>
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@@ -4426,7 +4422,6 @@ <h3 style="margin:7px">Volume of a pyramid</h3>
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@@ -4565,6 +4560,7 @@ <h3 style="margin:7px">Volume of a horizontal frustum pyramid</h3>
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@@ -4949,8 +4945,8 @@ <h3 style="margin:7px">Volume of a tetrahedron</h3>
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