document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=663690>Question 663690</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve:\r<BR>\n" );
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document.write( "X^4 + 100 = 0\r<BR>\n" );
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document.write( "The problem is that the students only have factoring, irrational, and complex numbers as their background.\r<BR>\n" );
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document.write( "Let a = x^2\r<BR>\n" );
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document.write( "a^2 = -50<BR>\n" );
document.write( "a = 5i*{sqrt(2)}<BR>\n" );
document.write( "x^2 = 5i*{sqrt(2)}\r<BR>\n" );
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document.write( "How to find x? \r<BR>\n" );
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document.write( "Use synthetic division and guess? That doesn't seem to work too well either? \r<BR>\n" );
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document.write( "Recommendations for new Algebra II students? Thanks. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #412886 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=412886\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Solve:\r<BR>\n" );
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document.write( "X^4 + 100 = 0<BR>\n" );
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document.write( "Use DeMoivre's Theorem<BR>\n" );
document.write( "x^4 = 100cis(180) + n*360<BR>\n" );
document.write( "x = sqrt(10)cis(45) + n*90<BR>\n" );
document.write( "x = sqrt(10)cis(45), ...cis(135), cis(225), cis(315)<BR>\n" );
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document.write( "Probably more than Algebra 2 can do, tho.<BR>\n" );
document.write( "--> not an appropriate problem for Algebra 2.\r<BR>\n" );
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