document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=894070>Question 894070</A>: <I><SPAN STYLE=\"word-break: break-all;\"> prove that if a product of two positive numbers is greater than their sum,then the sum is greater than four </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #542641 by </B><A HREF=/tutors/aboutme.mpl?userid=richard1234><B>richard1234(7193)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richard1234><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=richard1234><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=542641\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let a and b be the numbers.\r<BR>\n" );
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document.write( "If ab > a + b, then ab - a - b > 0 <--> (a-1)(b-1) > 1.\r<BR>\n" );
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document.write( "Let x = a-1, y = b-1. a+b > 4 if and only if x+y > 2. The problem reduces to showing that if xy > 1, then x+y > 2, however this is fairly easy to show.\r<BR>\n" );
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