document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=255806>Question 255806</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Polynomial equations help!\r<BR>\n" );
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document.write( "x^4-2x^2+1=0 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #188038 by </B><A HREF=/tutors/aboutme.mpl?userid=Greenfinch><B>Greenfinch(383)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Greenfinch><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=Greenfinch><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=188038\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> This is a quadratic in x^2. The easiest way to see this is to put y = x^2 so that can now re-write as y^2 -2y +1 = 0 which factorises to<BR>\n" );
document.write( "(y- 1)^2 = 0<BR>\n" );
document.write( "so y = 1<BR>\n" );
document.write( "Thus x^2 = 1<BR>\n" );
document.write( "There are therefore four answers, all the same with x=1 </SPAN>\n" );
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