document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1085917>Question 1085917</A>: <I><SPAN STYLE=\"word-break: break-all;\"> please help me thank you. write the product as a sum using a product to sum identity. 2sin(x+6y)cos(x-6y). </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #700028 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=700028\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font color=\"black\" face=\"times\" size=\"3\">The trig identity we'll use is <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \sin(\alpha)\cos(\beta) = \frac{1}{2}\left(\sin(\alpha+\beta)+\sin(\alpha-\beta)\right)\"><BR>\n" );
document.write( "which is from this <a  rel=nofollow HREF=\"http://tutorial.math.lamar.edu/pdf/Trig_Cheat_Sheet.pdf\">list of trig identities</a> (see the \"Product to Sum Formulas\" section on page 2)\r<BR>\n" );
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document.write( "In this case,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \alpha\"> = alpha = x+6y<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \beta\"> = beta = x-6y\r<BR>\n" );
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document.write( "So this means,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \sin(\alpha)\cos(\beta) = \frac{1}{2}\left(\sin(\alpha+\beta)+\sin(\alpha-\beta)\right)\"><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \sin(x+6y)\cos(x-6y) = \frac{1}{2}\left(\sin(x+6y+x-6y)+\sin(x+6y-(x-6y))\right)\"><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \sin(x+6y)\cos(x-6y) = \frac{1}{2}\left(\sin(2x)+\sin(x+6y-x+6y)\right)\"><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \sin(x+6y)\cos(x-6y) = \frac{1}{2}\left(\sin(2x)+\sin(12y)\right)\"><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \sin(x+6y)\cos(x-6y) = \frac{1}{2}\sin(2x)+\frac{1}{2}\sin(12y)\"><BR>\n" );
document.write( "</font> </SPAN>\n" );
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