document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=651946>Question 651946</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 2cotx/1+cot^2(x)=sin2x </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #407861 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=407861\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Prove<BR>\n" );
document.write( "2cotx/(1+cot^2(x))=sin2x<BR>\n" );
document.write( "start with left side<BR>\n" );
document.write( "2cos/sin/(1+cos^2/sin^2)<BR>\n" );
document.write( "2cos/sin/(sin^2+cos^2)/sin^2)<BR>\n" );
document.write( "2cos/sin/(1/sin^2)<BR>\n" );
document.write( "2sinxcosx=sin2x<BR>\n" );
document.write( "verified: left side=right side </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );