document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=499494>Question 499494</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Use the given information to find each value.<BR>\n" );
document.write( "sint=(-12/13)     &#960; < t < 3&#960;/2\r<BR>\n" );
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document.write( "(a) cos 2t\r<BR>\n" );
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document.write( "(b) sin 2t\r<BR>\n" );
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document.write( "(c) cos(t/2)\r<BR>\n" );
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document.write( "(d) sin(t/2) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #337745 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=337745\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Use the given information to find each value.<BR>\n" );
document.write( "sint=(-12/13) &#960; < t < 3&#960;/2 <BR>\n" );
document.write( "(a) cos 2t <BR>\n" );
document.write( "(b) sin 2t <BR>\n" );
document.write( "(c) cos(t/2) <BR>\n" );
document.write( "(d) sin(t/2) <BR>\n" );
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document.write( "sint=(-12/13)<BR>\n" );
document.write( "You are working with 5-12-13 right triangle in quadrant III where sin and cos are<0<BR>\n" );
document.write( "cost=(-5/13)<BR>\n" );
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document.write( "(a) cos 2t=cos^2t-sin^2t=(-5/13)^2-(-12/13)^2=0.1479-0.8521=-0.7042<BR>\n" );
document.write( "(b) sin 2t=2sintcost=2(-12/13)(-5/13)=0.7101 <BR>\n" );
document.write( "(c) cos(t/2)=±&#8730;((1+cost)/2)=-&#8730;((1-5/13)/2)=-&#8730;0.3077=-0.5547 (choose negative root because t/2 is in quadrant II where cos is <0<BR>\n" );
document.write( "(d) sin(t/2)=±&#8730;((1-cost)/2)=&#8730;((1+5/13)/2)=&#8730;0.6923=0.8320 (choose positive root because t/2 is in quadrant II where sin is >0 </SPAN>\n" );
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