document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=680225>Question 680225</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Let sin(A) = 3/5 with A in QII. What is the exact value of sin(2A) using an identity. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #422272 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=422272\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let sin(A) = 3/5 with A in QII. What is the exact value of sin(2A) using an identity.<BR>\n" );
document.write( "sinA=3/5 (you are working with a 3-4-5 right triangle)<BR>\n" );
document.write( "cosA=-4/5<BR>\n" );
document.write( "Identity: <BR>\n" );
document.write( "sin2A=2sinAcosA=2*(3/5)*(-4/5)=-24/25<BR>\n" );
document.write( "..<BR>\n" );
document.write( "check: with calculator<BR>\n" );
document.write( "A=arcsin(3/5)=143.13º (in QII)<BR>\n" );
document.write( "2A=286.26º<BR>\n" );
document.write( "sin2A=sin(286.26)&#8776;-0.96<BR>\n" );
document.write( "-24/25=-0.96<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );