document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1043641>Question 1043641</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find, in terms of &#960;, the surface area of a sphere generated by rotating a semicircle of radius 6 inches about its diameter. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #658827 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=658827\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Without loss of generality, let the semicircle of radius 6 be represented by the equation\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+sqrt%2836-x%5E2%29 ALIGN=MIDDLE  ALT=\"y+=+sqrt%2836-x%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "Then the surface area is obtained by rotating a rectangle with radius <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y+=+sqrt%2836-x%5E2%29 ALIGN=MIDDLE  ALT=\"y+=+sqrt%2836-x%5E2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > and width dx around the x-axis.  <BR>\n" );
document.write( "The element of surface area is then given by \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=dA+=+2%2Api%2Asqrt%2836-x%5E2%29dx ALIGN=MIDDLE  ALT=\"dA+=+2%2Api%2Asqrt%2836-x%5E2%29dx\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "The surface area is gotten by adding this infinite number of infinitesimal elements of surface area--\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A+=+int%281%2CdA%2C-6%2C6%29+=+2%2Aint%282%2Api%2Asqrt%2836-x%5E2%29%2Cdx%2C0%2C6%29+=+4%2Api%2Aint%28sqrt%2836-x%5E2%29%2Cdx%2C0%2C6%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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