document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=239705>Question 239705</A>: <I><SPAN STYLE=\"word-break: break-all;\"> PLEASE, PLEASE HELP ME!!!\r<BR>\n" );
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document.write( "Given <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+5x%5E4+-+3x%5E3+%2B+ax%5E2+%2B+bx+-+7+=+0+ ALIGN=MIDDLE  ALT=\"+5x%5E4+-+3x%5E3+%2B+ax%5E2+%2B+bx+-+7+=+0+\"   DISABLED_style= \"max-width:90%; height:auto;\" > determine a and b so that i is a zero of the quartic.\r<BR>\n" );
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document.write( "THANK YOU FOR ANY HELP YOU CAN GIVE!!!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #175873 by </B><A HREF=/tutors/aboutme.mpl?userid=edjones><B>edjones(8007)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=edjones><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=edjones><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=175873\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 5x^4 - 3x^3 + ax^2 + bx - 7 = 0<BR>\n" );
document.write( "f(i)=5-3(-i)-a+bi-7=0 <BR>\n" );
document.write( "-3(-i)-a+bi=2 because 5-7=-2<BR>\n" );
document.write( "-3(-i)+bi=2+a<BR>\n" );
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document.write( "f(-i)=5-3i-a+b(-i)-7=0 If one zero is i then another must be -i.<BR>\n" );
document.write( "-3i-a+b(-i)=2<BR>\n" );
document.write( "-3i+b(-i)=2+a<BR>\n" );
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document.write( "-3(-i)+bi=-3i+b(-i) Since they both equal 2+a.<BR>\n" );
document.write( "-3-b=3+b multiply each side by i.<BR>\n" );
document.write( "2b=-6 <BR>\n" );
document.write( "b=-3<BR>\n" );
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document.write( "a=-3(-i)-3i-2<BR>\n" );
document.write( "a=-2<BR>\n" );
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document.write( "It checks.<BR>\n" );
document.write( "This WAS tough!<BR>\n" );
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document.write( "Ed </SPAN>\n" );
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