document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=163638>Question 163638</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I wanted you to check my answers on these two problems:\r<BR>\n" );
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document.write( "1) Problem: (2-4i)(2-i)<BR>\n" );
document.write( "    4-2i-4i-4i^2<BR>\n" );
document.write( "    4-6i-4i^2<BR>\n" );
document.write( "    4-6i-4i^2(-1)<BR>\n" );
document.write( "    4-6i+4<BR>\n" );
document.write( " answer: 8-6i\r<BR>\n" );
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document.write( "2)  Problem:  3+5i/1+i<BR>\n" );
document.write( "       3+5i/1+i . i/i<BR>\n" );
document.write( "       3i+5i^2/i+i^2<BR>\n" );
document.write( "   3i+5(-1)/i+i(-1) = -3i-5/-1-1 = <BR>\n" );
document.write( " answer:  -3i-5/-2i\r<BR>\n" );
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document.write( "Thanks.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #120538 by </B><A HREF=/tutors/aboutme.mpl?userid=gonzo><B>gonzo(654)</B></A><img src=\"/images/stars/stars-11.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=gonzo><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=120538\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> i don't get the answers you do.<BR>\n" );
document.write( "here's what i did.<BR>\n" );
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document.write( "problem 1:<BR>\n" );
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document.write( "(2-4i)*(2-i)<BR>\n" );
document.write( "using FOIL<BR>\n" );
document.write( "First..(F) = 2*2 = 4<BR>\n" );
document.write( "Outer..(O) = 2*-i = -2i<BR>\n" );
document.write( "Inner..(I) = -4i*2 = -8i<BR>\n" );
document.write( "Last...(L) = -4i*-i = +4i^2<BR>\n" );
document.write( "adding like terms together gets<BR>\n" );
document.write( "4 - 10i + 4i^2<BR>\n" );
document.write( "i^2 = -1 so 4i^2 becomes -4<BR>\n" );
document.write( "equation then becomes<BR>\n" );
document.write( "4 - 10i - 4<BR>\n" );
document.write( "which becomes -10i<BR>\n" );
document.write( "answer looks like it should be -10i<BR>\n" );
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document.write( "problem 2:<BR>\n" );
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document.write( "(3+5i)/(1+i)<BR>\n" );
document.write( "multiply numerator and denominator by (1-i) and equation becomes<BR>\n" );
document.write( "((3+5i)*(1-i))/((1+i)*(1-i))<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "using FOIL to multiply numerator gets<BR>\n" );
document.write( "numerator = (3+5i)*(1-i)<BR>\n" );
document.write( "First = 3*1 = 3<BR>\n" );
document.write( "Outer = 3*-i = -3i<BR>\n" );
document.write( "Inner = 5i*1 = +5i<BR>\n" );
document.write( "Last = 5i*-i = -5i^2<BR>\n" );
document.write( "combining like terms and numerator becomes<BR>\n" );
document.write( "3 + 2i - 5i^2<BR>\n" );
document.write( "since i^2 = -1, numerator becomes<BR>\n" );
document.write( "3 + 2i - 5*(-1)<BR>\n" );
document.write( "which becomes<BR>\n" );
document.write( "3 + 2i + 5<BR>\n" );
document.write( "which becomes<BR>\n" );
document.write( "8 + 2i<BR>\n" );
document.write( "numerator = 8+2i<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "using FOIL to multiply denominator gets<BR>\n" );
document.write( "denominator = (1-i)*(1+i)<BR>\n" );
document.write( "First = 1*1 = 1<BR>\n" );
document.write( "Outer = 1*i = i<BR>\n" );
document.write( "Inner = -i*1 = -i<BR>\n" );
document.write( "Last = -i*i = -i^2<BR>\n" );
document.write( "combining like terms and denominator becomes<BR>\n" );
document.write( "1-i^2<BR>\n" );
document.write( "since i^2 = -1 denominator becomes<BR>\n" );
document.write( "1-(-1)<BR>\n" );
document.write( "which becomes<BR>\n" );
document.write( "1+1<BR>\n" );
document.write( "which becomes<BR>\n" );
document.write( "2<BR>\n" );
document.write( "denominator = 2<BR>\n" );
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document.write( "putting numerator and denominator back into the total equation and it becomes<BR>\n" );
document.write( "(8+2i)/2<BR>\n" );
document.write( "which becomes 4+i<BR>\n" );
document.write( "answer looks like it should be 4+i<BR>\n" );
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document.write( " </SPAN>\n" );
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