document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1087889>Question 1087889</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Rewrite as a single expression. cos(9theta)cos(6theta)-sin(9theta)sin(6theta)\r<BR>\n" );
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document.write( "Select one:\r<BR>\n" );
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document.write( "a. cos(15theta)<BR>\n" );
document.write( "b. sin(14theta)<BR>\n" );
document.write( "c. sin(6theta)<BR>\n" );
document.write( "d. cos(14theta) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #702170 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52835)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=702170\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "Rewrite as a single expression. cos(9theta)cos(6theta)-sin(9theta)sin(6theta)\r<BR>\n" );
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document.write( "Select one:\r<BR>\n" );
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document.write( "<PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\">\r\n" );
document.write( "a. cos(15theta)    <<<---=== This and only this (9 + 6 = 15).\r\n" );
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document.write( "b. sin(14theta)\r\n" );
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document.write( "c. sin(6theta)\r\n" );
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document.write( "d. cos(14theta)\r\n" );
document.write( "</PRE>\r<BR>\n" );
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document.write( " </SPAN>\n" );
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