document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=79573>Question 79573</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0618558845/algebrahomeworkh>Geometry Reasoning</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> Write an indirect proof. If n/2 is an integer, then n is even. <BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #86587 by </B><A HREF=/tutors/aboutme.mpl?userid=wgunther><B>wgunther(43)</B></A><img src=\"/images/stars/stars-07.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=wgunther><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=86587\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Lemma: if n/2 is an integer, n is an integer. <BR>\n" );
document.write( "Proof: Unproved, pretty intuitive.\r<BR>\n" );
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document.write( "Theorem: if n/2 is an integer, n is even.<BR>\n" );
document.write( "Proof: Suppose n isn't even. Then n is odd, as n is an integer, and all integers are dichotomous (even or odd). Then n=2k+1, where k is an integer. (2k+1)/2 = k+1/2. This isn't an integer. -><-, contradiction. Therefore, n is even.  </SPAN>\n" );
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