document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=983612>Question 983612</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Can you help battle with this;  Given ; sin(x+y) = sin x cos y +cos x sin y  and cos (x+y) =cos x cos y -sin x sin y  ; derive a formula for cot (x+y). </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #604383 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=604383\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> cot = cos/sin<BR>\n" );
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