document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=421994>Question 421994</A>: <I><SPAN STYLE=\"word-break: break-all;\"> PROVE:<BR>\n" );
document.write( "1+tan(U)/1-tan(U)= cot(U)+1/cot(U)-1 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #294763 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=294763\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 1+tan(U)/1-tan(U)= cot(U)+1/cot(U)-1\r<BR>\n" );
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document.write( "..<BR>\n" );
document.write( "starting with left side,\r<BR>\n" );
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document.write( "1+tan/1-tan<BR>\n" );
document.write( "using identity tan=1/cot<BR>\n" );
document.write( "=1+1/cot/1-1/cot<BR>\n" );
document.write( "=((cot+1)/cot)/((cot-1)/cot)<BR>\n" );
document.write( "cancelling cot in denominator<BR>\n" );
document.write( "=cot+1/cot-1<BR>\n" );
document.write( "verified: left side = right side </SPAN>\n" );
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