document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1040074>Question 1040074</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Prove by identity<BR>\n" );
document.write( "A u (A n B)= A </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #654878 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52781)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=654878\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "Prove <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28cross%28by%29%29 ALIGN=MIDDLE  ALT=\"highlight%28cross%28by%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > an identity<BR>\n" );
document.write( "A u (A n B)= A<BR>\n" );
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document.write( "Let x be any element from the left side set. Then x belongs to A, to the right side set.\r<BR>\n" );
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document.write( "Let y be any element of A, which is right side set. Then y belongs to the left side set.\r<BR>\n" );
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document.write( "Thus we proved that every element of the left side set belongs to the right side set, and opposite, <BR>\n" );
document.write( "that every element of the right side set belongs to the left side set.\r<BR>\n" );
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document.write( "It means that the two sets are equal.\r<BR>\n" );
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document.write( "The proof is completed.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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