document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1106840>Question 1106840</A>: <I><SPAN STYLE=\"word-break: break-all;\"> zz*+3(z-z*)=13+12i </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #721820 by </B><A HREF=/tutors/aboutme.mpl?userid=rothauserc><B>rothauserc(4718)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rothauserc><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=rothauserc><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=721820\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let z = a + bi<BR>\n" );
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document.write( "I assume by z*, you mean the complex conjugate of z, then<BR>\n" );
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document.write( "z* = a - bi<BR>\n" );
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document.write( "zz* = (a + bi)(a - bi) = a^2 -abi +abi -(b^2)(i^2) = a^2 +b^2<BR>\n" );
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document.write( "Note that i^2 = -1<BR>\n" );
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document.write( "3(z-z*) = 3(a+bi - a-bi) = 3(2bi) = 6bi<BR>\n" );
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document.write( "a^2 +b^2 +6bi = (a^2+b^2) +6bi<BR>\n" );
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document.write( "b = 2<BR>\n" );
document.write( "a = 3<BR>\n" );
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document.write( "z = 3 +2i<BR>\n" );
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document.write( " </SPAN>\n" );
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