document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=453268>Question 453268</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I would appreciate some help verifying this identity:\r<BR>\n" );
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document.write( "tan((-pi/2)+x)=-cot x\r<BR>\n" );
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document.write( "It may not be verifiable.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #311436 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=311436\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> verifying this identity: <BR>\n" );
document.write( "tan((-pi/2)+x)=-cot x <BR>\n" );
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document.write( "Left side change:<BR>\n" );
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document.write( "[(tan(-pi/2)+tan(x))/(1-tan(-pi/2)*tan(x)] = -cot(x)<BR>\n" );
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document.write( "Simplify left side:<BR>\n" );
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document.write( "Comment: tan(-pi/2) is undefined, so the left side is undefined<BR>\n" );
document.write( "and cannot equal the right side.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.  </SPAN>\n" );
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