document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1172165>Question 1172165</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the exact values of  sin(2u), cos(2u), and tan(2u) using the double-angle formulas.\r<BR>\n" );
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document.write( "csc(u) = 6,   0 < u < 𝜋/2\r<BR>\n" );
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document.write( "sin(2u)	 = 	<BR>\n" );
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document.write( "cos(2u)	 = 	<BR>\n" );
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document.write( "tan(2u)	 = </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #797089 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=797089\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> sin 2u=2 sin u  cos u;<BR>\n" );
document.write( "csc u =6, sin u =1/6, u=9.59 degrees<BR>\n" );
document.write( "cos u has to be sqrt(35)/6<BR>\n" );
document.write( "sin 2u=2 sqrt(35)/36=sqrt(35)/18<BR>\n" );
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document.write( "cos (2u)=cos ^2 u-sin^2 u<BR>\n" );
document.write( "=(35/36)-(1/36)=17/18<BR>\n" );
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document.write( "tan 2u= sin 2u / cos 2u<BR>\n" );
document.write( "=sqrt(35)/17<BR>\n" );
document.write( "or 2 tan (u)/1-tan^2 (u)<BR>\n" );
document.write( "where tan u = 1/sqrt(35)=sqrt(35)/35<BR>\n" );
document.write( "so 2 sqrt(35)/35/1-35/35^2; the denominator is (35^2-35/35^2)<BR>\n" );
document.write( "this will become 2 sqrt(35)*35/1190, and that is 2 sqrt(35)/34 or sqrt(35)/17), same as above. sin u/ cos u is easier, since those have already been obtained. </SPAN>\n" );
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