document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=971581>Question 971581</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the value of tan2 x on the interval (0,2pi) given cos x = (5/9) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #594595 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=594595\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Find the value of tan2 x on the interval (0,2pi) given cos x = (5/9)<BR>\n" );
document.write( "sinx=&#8730;(1-cos^2(x))=&#8730;(1-25/81)=&#8730;(56/81)=&#8730;56/9<BR>\n" );
document.write( "sin(2x)=2sinxcosx=2&#8730;56/9*5/9=10&#8730;56/81<BR>\n" );
document.write( "cos(2x)=cos^2(x)-sin^2(x)=25/81-56/81=-31/81<BR>\n" );
document.write( "tan(2x)=sin(2x)/cos(2x)=-(10&#8730;56)/31 </SPAN>\n" );
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