document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=641428>Question 641428</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Verify the identity.\r<BR>\n" );
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document.write( "sin (x + y) - sin (x - y) = 2 cos x sin y \r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #403657 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=403657\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> sin(x + y) - sin(x - y) = 2cos(x)sin(y)\r<BR>\n" );
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document.write( "sin(x)cos(y) + cos(x)sin(y) - (sin(x)cos(y) - cos(x)sin(y)) = 2cos(x)sin(y)\r<BR>\n" );
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document.write( "sin(x)cos(y) + cos(x)sin(y) - sin(x)cos(y) + cos(x)sin(y) = 2cos(x)sin(y)\r<BR>\n" );
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document.write( "2cos(x)sin(y) = 2cos(x)sin(y)\r<BR>\n" );
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document.write( "So that verifies the identity </SPAN>\n" );
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