document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=325607>Question 325607</A>: <I><SPAN STYLE=\"word-break: break-all;\"> b = ( a^x + a^-x )/ 2 find x </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #233134 by </B><A HREF=/tutors/aboutme.mpl?userid=Jk22><B>Jk22(389)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Jk22><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=Jk22><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=233134\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> b = ( a^x + a^-x )/ 2=cosh(xln(a))\r<BR>\n" );
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document.write( "=> x=acosh(b)/ln(a)\r<BR>\n" );
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document.write( "or 2ba^x=a^(2x)+1 => a^(2x)-2b*a^x+1=0\r<BR>\n" );
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document.write( "a^x=(2b+-sqrt(4b^2-4)/2=b+-sqrt(b^2-1)\r<BR>\n" );
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document.write( "x=ln(b+-sqrt(b^2-1))/ln(a) </SPAN>\n" );
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