document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1074376>Question 1074376</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If sinA= -3/5 with A in quadrant 3, find the following:\r<BR>\n" );
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document.write( "A.)cos A/2<BR>\n" );
document.write( "B.)sin A/2<BR>\n" );
document.write( "c.)sec A/2<BR>\n" );
document.write( "d.)csc A/2 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #689106 by </B><A HREF=/tutors/aboutme.mpl?userid=sachi><B>sachi(548)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=sachi><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=sachi><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=689106\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If sinA= -3/5 with A in quadrant 3, find the following:\r<BR>\n" );
document.write( "\n" );
document.write( "A.)cos A/2<BR>\n" );
document.write( "B.)sin A/2<BR>\n" );
document.write( "c.)sec A/2<BR>\n" );
document.write( "d.)csc A/2\r<BR>\n" );
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document.write( "we know cosA=sqrt(1-sin^2A)=sqrt(1-9/25)=-4/5 (3 quadrant)<BR>\n" );
document.write( "we also know that cosA= 2cos^2A/2-1=1-2sin^2A/2<BR>\n" );
document.write( "so 2cos^2A/2-1=-4/5<BR>\n" );
document.write( "or 2cos^2A/2=1-4/5=1/5<BR>\n" );
document.write( "or cos^2A/2=1/10<BR>\n" );
document.write( "or cosA/2=-sqrt(1/10)..A<BR>\n" );
document.write( "& secA/2=-sqrt10 .......C<BR>\n" );
document.write( "now<BR>\n" );
document.write( "1-2sin^2A/2=-4/5<BR>\n" );
document.write( "2sin^2A/2=1+4/5=9/5<BR>\n" );
document.write( "sin^2A/2=9/10<BR>\n" );
document.write( "sinA/2=-sqrt(9/10)=-3/sqrt10..B<BR>\n" );
document.write( "& cscA/2=-sqrt10/3 .......D<BR>\n" );
document.write( "ok<BR>\n" );
document.write( " </SPAN>\n" );
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