document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=979506>Question 979506</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the exact value by using a half-angle identity. (4 points) <BR>\n" );
document.write( "cos(5pi/12)\r<BR>\n" );
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document.write( "Here is my work, can someone please check to see if I did it right?\r<BR>\n" );
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document.write( "cos ((5 pi/6)/2) = +/- sqrt( (1+cos (5 pi/6))/2 )<BR>\n" );
document.write( "cos(5 pi/6) = -sqrt(3)/2<BR>\n" );
document.write( "cos (5 pi/12) = +/- sqrt( (2/2-sqrt(3)/2)/2 )<BR>\n" );
document.write( "cos (5 pi/12) = +/- sqrt( ((2-sqrt(3))/2)/2 )<BR>\n" );
document.write( "cos (5 pi/12) = sqrt( ( (2-sqrt(3))/4 ) )<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 #600795 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52799)</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=600795\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> \r<BR>\n" );
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document.write( "Find the exact value by using a half-angle identity. (4 points) <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos%285pi%2F12%29 ALIGN=MIDDLE  ALT=\"cos%285pi%2F12%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "Here is my work, can someone please check to see if I did it right? \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos+%28%285pi%2F6%29%2F2%29 ALIGN=MIDDLE  ALT=\"cos+%28%285pi%2F6%29%2F2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = +/- <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28+%281%2Bcos+%285pi%2F6%29%29%2F2+%29 ALIGN=MIDDLE  ALT=\"sqrt%28+%281%2Bcos+%285pi%2F6%29%29%2F2+%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > &nbsp;&nbsp;&nbsp;&nbsp;correct\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos%285pi%2F6%29 ALIGN=MIDDLE  ALT=\"cos%285pi%2F6%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-sqrt%283%29%2F2 ALIGN=MIDDLE  ALT=\"-sqrt%283%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;correct\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos+%285pi%2F12%29 ALIGN=MIDDLE  ALT=\"cos+%285pi%2F12%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = +/- <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28+%282%2F2-sqrt%283%29%2F2%29%2F2+%29 ALIGN=MIDDLE  ALT=\"sqrt%28+%282%2F2-sqrt%283%29%2F2%29%2F2+%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;correct\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos+%285+pi%2F12%29 ALIGN=MIDDLE  ALT=\"cos+%285+pi%2F12%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = +/- <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28+%28%282-sqrt%283%29%29%2F2%29%2F2+%29 ALIGN=MIDDLE  ALT=\"sqrt%28+%28%282-sqrt%283%29%29%2F2%29%2F2+%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;correct\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos+%285pi%2F12%29 ALIGN=MIDDLE  ALT=\"cos+%285pi%2F12%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28+%282-sqrt%283%29%29%2F4+%29 ALIGN=MIDDLE  ALT=\"sqrt%28+%282-sqrt%283%29%29%2F4+%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;correct\r<BR>\n" );
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document.write( "EVERYTHING IS CORRECT.<BR>\n" );
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document.write( "You can write the last expression as \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos+%285pi%2F12%29 ALIGN=MIDDLE  ALT=\"cos+%285pi%2F12%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%282-sqrt%283%29%29%2F2 ALIGN=MIDDLE  ALT=\"sqrt%282-sqrt%283%29%29%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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