document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=549871>Question 549871</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If sin x = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=12%2F13 ALIGN=MIDDLE  ALT=\"12%2F13\"   DISABLED_style= \"max-width:90%; height:auto;\" > where <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=pi%2F2+%3C=+x+%3C=+pi ALIGN=MIDDLE  ALT=\"pi%2F2+%3C=+x+%3C=+pi\"   DISABLED_style= \"max-width:90%; height:auto;\" >, determine:\r<BR>\n" );
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document.write( "a) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin+%28x%2F2%29 ALIGN=MIDDLE  ALT=\"sin+%28x%2F2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "b) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sec+%28x%2F2%29 ALIGN=MIDDLE  ALT=\"sec+%28x%2F2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #358185 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=358185\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If sin x =12/13, where pi/2 <= x <= pi, determine:<BR>\n" );
document.write( "a) sin (x/2)<BR>\n" );
document.write( "b) sec (x/2)<BR>\n" );
document.write( "..<BR>\n" );
document.write( "You are working with a reference angle in quadrant II where sin>0 and cos<0<BR>\n" );
document.write( "sin x=12/13 (given)<BR>\n" );
document.write( "cosx=-5/13<BR>\n" );
document.write( "..<BR>\n" );
document.write( "a) Using half-angle formula for sin<BR>\n" );
document.write( "sin x/2=&#8730;[(1-cosx)/2]=&#8730;[(1+5/13)/2]=&#8730;[(18/13)/2]=&#8730;[(18/26]<BR>\n" );
document.write( "..<BR>\n" );
document.write( "b) Using half-angle formula for cos then taking the reciprocal<BR>\n" );
document.write( "cos x/2=-&#8730;[(1-cosx)/2]=-&#8730;[(1-5/13)/2]=-&#8730;[(8/13)/2]=-&#8730;[(8/26]<BR>\n" );
document.write( "sec x/2=1/(cos x/2)=-&#8730;(26/8) </SPAN>\n" );
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