document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1105377>Question 1105377</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A is a reflexive angle whose sin is -5/13. Find:\r<BR>\n" );
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document.write( "1. sin (2A)<BR>\n" );
document.write( "2. cos (2A)<BR>\n" );
document.write( "3. sin (4A<BR>\n" );
document.write( "4. cos (4A)\r<BR>\n" );
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document.write( "Show your calculations. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #720208 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=720208\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A is a reflexive angle whose sin is -5/13. <BR>\n" );
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document.write( "The terminal point is in Q4 at (12,-5)<BR>\n" );
document.write( "x = 12<BR>\n" );
document.write( "y = -5<BR>\n" );
document.write( "r = 13<BR>\n" );
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document.write( "Find:\r<BR>\n" );
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document.write( "1. sin (2A)<BR>\n" );
document.write( "sin(2A) = 2sin(A)*cos(A)<BR>\n" );
document.write( "cos(a) = x/r = 12/13<BR>\n" );
document.write( "sin(2A) = 2(-5/13)*(13/13) = -10/169<BR>\n" );
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document.write( "2. cos (2A)<BR>\n" );
document.write( "cos(2A) = sqrt(1 - sin^2(2A))<BR>\n" );
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document.write( "3. sin (4A)<BR>\n" );
document.write( "Same as #1<BR>\n" );
document.write( "4. cos (4A)<BR>\n" );
document.write( "Same as #2 </SPAN>\n" );
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