document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=622024>Question 622024</A>: <I><SPAN STYLE=\"word-break: break-all;\"> please help me find the exact value of\r<BR>\n" );
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document.write( "tan2u\r<BR>\n" );
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document.write( "given: sinu= -4/5 & pi < u < 3pi/2 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #391408 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=391408\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> find the exact value of <BR>\n" );
document.write( "tan2u <BR>\n" );
document.write( "given: sinu= -4/5 & pi < u < 3pi/2<BR>\n" );
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document.write( "sinu=-4/5 in quadrants III and IV where sin<0<BR>\n" );
document.write( "since quadrant IV is not in the domain,(&#960;,3&#960;/2), reference angle is in quadrant III<BR>\n" );
document.write( "sinu=-4/5=opposite side/hypotenuse<BR>\n" );
document.write( "adjacent side=3 since you are working with a 3-4-5 right triangle<BR>\n" );
document.write( "tanu=opposite side/adjacent side=4/3 in quadrant III where tan>0<BR>\n" );
document.write( "tan2u=2tanu/(1-tan^2u)=2*4/3/(1-(4/3)^2)=(8/3)/(1-16/9)=(8/3)/(-7/9)=-72/21 </SPAN>\n" );
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