document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=888541>Question 888541</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Suppose that tan(t)=-12/5 where t is in the second quadrant. Find cos(2t). </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #537451 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=537451\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Suppose that tan(t)=-12/5 where t is in the second quadrant. Find cos(2t).<BR>\n" );
document.write( "You are working with a (5/12/13) reference right triangle in quadrant II<BR>\n" );
document.write( "sin(t)=12/13<BR>\n" );
document.write( "cos(2t)=1-2sin^2(t)<BR>\n" );
document.write( "=-(1-(12/13)^2)<BR>\n" );
document.write( "=-(1-144/169)<BR>\n" );
document.write( "cos(2t)=-(25/69) </SPAN>\n" );
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