document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1062528>Question 1062528</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F%28a%2Bu%29%2B1%2F%28b%2Bu%29%2B1%2F%28c%2Bu%29%2B1%2F%28d%2Bu%29=2%2Fu ALIGN=MIDDLE  ALT=\"1%2F%28a%2Bu%29%2B1%2F%28b%2Bu%29%2B1%2F%28c%2Bu%29%2B1%2F%28d%2Bu%29=2%2Fu\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F%28a%2Bv%29%2B1%2F%28b%2Bv%29%2B1%2F%28c%2Bv%29%2B1%2F%28d%2Bv%29=2%2Fv ALIGN=MIDDLE  ALT=\"1%2F%28a%2Bv%29%2B1%2F%28b%2Bv%29%2B1%2F%28c%2Bv%29%2B1%2F%28d%2Bv%29=2%2Fv\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<BR>\n" );
document.write( "Where u and v are imaginary cube roots of unity and a, b, c, d are constants,<BR>\n" );
document.write( "then prove that<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F%28a%2B1%29%2B1%2F%28b%2B1%29%2B1%2F%28c%2B1%29%2B1%2F%28d%2B1%29=2 ALIGN=MIDDLE  ALT=\"1%2F%28a%2B1%29%2B1%2F%28b%2B1%29%2B1%2F%28c%2B1%29%2B1%2F%28d%2B1%29=2\"   DISABLED_style= \"max-width:90%; height:auto;\" >,<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #677541 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52802)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=677541\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "The competent mathematician will never write \r<BR>\n" );
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document.write( "\". . .  imaginary cube roots of unity\",\r<BR>\n" );
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document.write( "because they are not imaginary. They are COMPLEX instead.\r<BR>\n" );
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document.write( "What is the source of this problem ?\r<BR>\n" );
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document.write( "I just saw this problem once (long time ago) in this forum and worked on it.\r<BR>\n" );
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document.write( "And my conclusion was: the formulation is wrong/incorrect.\r<BR>\n" );
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document.write( "So, my question is: WHAT IS THE SOURCE OF IT ?\r<BR>\n" );
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