document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=967167>Question 967167</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hello I really need help for this question,so if you guys can help I will be really appreciated. The question is I have to use a double-angle identity to find the exact value of cos x =12/13 and it said 0 degree<x<90degree find  sin 2x <BR>\n" );
document.write( "I don't get how this thing (0<x<90)involve in question and what is it telling me for. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #591133 by </B><A HREF=/tutors/aboutme.mpl?userid=tenkun><B>tenkun(12)</B></A><img src=\"/images/stars/stars-06.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=tenkun><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=591133\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> cos x =12/13\r<BR>\n" );
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document.write( "Sin^2x= 1- cos^2x<BR>\n" );
document.write( ".     = 1- 144/169<BR>\n" );
document.write( "      = 169/169 -144/169<BR>\n" );
document.write( "      = 25/169<BR>\n" );
document.write( "Sin x= &#8730;25/169<BR>\n" );
document.write( "     = 5/13\r<BR>\n" );
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document.write( "Sin 2x = 2*sin x * cos x<BR>\n" );
document.write( "       = 2 * 5/13 * 12/13<BR>\n" );
document.write( "       = 120/169 </SPAN>\n" );
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