document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1013017>Question 1013017</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve: x^4 -3x^2 =4 (find 4 roots)\r<BR>\n" );
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document.write( "* I plugged it into my calculator and only got two root -2 and 2. There should be two more but how do you get the answers with i? (my classmate's answer for that are x=i and x= -i) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #629168 by </B><A HREF=/tutors/aboutme.mpl?userid=macston><B>macston(5194)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=macston><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=macston><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=629168\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "let y=x^2 <BR>\n" );
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document.write( "x^4-3x^2=4<BR>\n" );
document.write( "x^4-3x^2-4=0 Replace x^2 with y.<BR>\n" );
document.write( "y^2-3y-4=0<BR>\n" );
document.write( "(y-4)(y+1)=0<BR>\n" );
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document.write( "y-4=0 or y+1=0<BR>\n" );
document.write( "y=4 or y=-1 . Replace y with x^2<BR>\n" );
document.write( "x^2=4 . or . x^2=-1<BR>\n" );
document.write( "x=+/-2 . or . x=+/-i  . (<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28-1%29=i ALIGN=MIDDLE  ALT=\"sqrt%28-1%29=i\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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