document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=928553>Question 928553</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the exact value of cos(t/2) if tan(t)= 12/5 and Pie < t < 3pie/2\r<BR>\n" );
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document.write( "a)2 Square root of 13/ 13<BR>\n" );
document.write( "b)3 Square root of 13/ 13<BR>\n" );
document.write( "c)-3/-2<BR>\n" );
document.write( "d)None of these<BR>\n" );
document.write( "e)7 Square root of 13/ 13<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 #564043 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=564043\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Find the exact value of cos(t/2) if tan(t)= 12/5 and Pie < t < 3pie/2 <BR>\n" );
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document.write( "working with (5-12-13) reference right triangle in quadrant III where cos<0, sin<0<BR>\n" );
document.write( "cos(t)=-5/13<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos%28t%2F2%29=-sqrt%28%281%2Bcost%29%2F2%29%0D%0A=-sqrt%28%281-%285%2F13%29%29%2F2%29%0D%0A=-sqrt%288%2F26%29=-sqrt%284%2F13%29=-2%2Fsqrt%2813%29=-2sqrt%2813%29%2F13 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "note:my ans is the same as that of a) except for the sign.<BR>\n" );
document.write( "cost=-5/13<BR>\n" );
document.write( "t=247.38&#730;<BR>\n" );
document.write( "t/2=123.69&#730; which is in quadrant II where cos<0  </SPAN>\n" );
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