document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=874623>Question 874623</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Could someone please show me the steps in solving this problem.\r<BR>\n" );
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document.write( "(e^7x - e^-7x)^2 - (e^7x + e^-7x)^2 / (e^7x + e^-7x)^2\r<BR>\n" );
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document.write( "The book says that the answer is -4 / (e^7x + e^-7x)^2\r<BR>\n" );
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document.write( "I don't know how they got -4 for the numerator. I am getting something completely different.\r<BR>\n" );
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document.write( "Thanks in advance. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #527616 by </B><A HREF=/tutors/aboutme.mpl?userid=mananth><B>mananth(16946)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mananth><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=mananth><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=527616\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28%28e%5E%287x%29+-+e%5E%28-7x%29%29%5E2+-+%28e%5E%287x%29+%2B+e%5E%28-7x%29%29%5E2%29+%2F+%28e%5E%287x%29+%2B+e%5E%28-7x%29%29%5E2%0D%0A ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "use the identity a^2-b^2= (a+b)(a-b)\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28%28e%5E%287x%29+-+e%5E%28-7x%29%29+%2B%28e%5E%287x%29+%2B+e%5E%28-7x%29%29%29%28e%5E%287x%29+-+e%5E%28-7x%29+-e%5E%287x%29+-+e%5E%28-7x%29%29+%2F+%28e%5E%287x%29+%2B+e%5E%28-7x%29%29%5E2%0D%0A ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2e%5E%287x%29%2A-2%28e%5E%28-7x%29%29%2F%28e%5E%287x%29+%2B+e%5E%28-7x%29%29%5E2 ALIGN=MIDDLE  ALT=\"2e%5E%287x%29%2A-2%28e%5E%28-7x%29%29%2F%28e%5E%287x%29+%2B+e%5E%28-7x%29%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "=<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-4%29%2F%28e%5E%287x%29+%2B+e%5E%28-7x%29%29%5E2 ALIGN=MIDDLE  ALT=\"%28-4%29%2F%28e%5E%287x%29+%2B+e%5E%28-7x%29%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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