document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1137787>Question 1137787</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Prove that cos35 + cos45 + cos75 + cos85 = 2cos5cos20 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #755689 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20850)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=755689\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> \r<BR>\n" );
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document.write( "prove that \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos%2835%29+%2B+cos%2845+%29%2B+cos%2875%29+%2B+cos%2885%29+=+2cos%285%29cos%2820+%29 ALIGN=MIDDLE  ALT=\"cos%2835%29+%2B+cos%2845+%29%2B+cos%2875%29+%2B+cos%2885%29+=+2cos%285%29cos%2820+%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos%28%287pi%29%2F36%29+%2B1%2Fsqrt%282%29%2B%28sqrt%283%29+-+1%29%2F%282+sqrt%282%29%29%2B+sin%28pi%2F36%29%3C%3E2+cos%28pi%2F36%29+cos%28pi%2F9%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "=> statement is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=FALSE ALIGN=MIDDLE  ALT=\"FALSE\"   DISABLED_style= \"max-width:90%; height:auto;\" > (the two sides are not equal) </SPAN>\n" );
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