document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=195803>Question 195803</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need help solving this problem\r<BR>\n" );
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document.write( "Factor completely\r<BR>\n" );
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document.write( "27b^4-64b\r<BR>\n" );
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document.write( "I came up with b(-27+8b^3) which is incorrect.... Not sure how to do it. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #146812 by </B><A HREF=/tutors/aboutme.mpl?userid=nerdybill><B>nerdybill(7384)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=nerdybill><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=nerdybill><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=146812\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 27b^4-64b <BR>\n" );
document.write( "Start by factoring out 3b:<BR>\n" );
document.write( "b(27b^3 - 64)<BR>\n" );
document.write( "Rewrite as:<BR>\n" );
document.write( "b((3b)^3 - 4^3)<BR>\n" );
document.write( "Notice, you now have a \"difference of cubes\".  This is a \"special\" factor.<BR>\n" );
document.write( "An expression of the form a3 - b3. The difference of two cubes factors into <BR>\n" );
document.write( "(a - b)(a^2 + ab + b^2). <BR>\n" );
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document.write( "So we can rewrite:<BR>\n" );
document.write( "b((3b)^3 - 4^3)<BR>\n" );
document.write( "as<BR>\n" );
document.write( "b(3b - 4)((3b)^2 + (3b)(4) + 4^2)<BR>\n" );
document.write( "b(3b - 4)(9b^2 + 12b + 16)\r<BR>\n" );
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