document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1174754>Question 1174754</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find sin(2a) when a terminates in quadrant II. cosa=-4/5. (I got -24/25, but I am not sure if I solved it correctly) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #800231 by </B><A HREF=/tutors/aboutme.mpl?userid=MathLover1><B>MathLover1(20850)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=MathLover1><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=MathLover1><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=800231\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "you got it right!\r<BR>\n" );
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document.write( "given:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%282a%29 ALIGN=MIDDLE  ALT=\"sin%282a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos%28a%29=-4%2F5 ALIGN=MIDDLE  ALT=\"cos%28a%29=-4%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "when a terminates in quadrant <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=II ALIGN=MIDDLE  ALT=\"II\"   DISABLED_style= \"max-width:90%; height:auto;\" >, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=0%3C=+a+%3C=180 ALIGN=MIDDLE  ALT=\"0%3C=+a+%3C=180\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "use identity:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%5E2%28a%29=1-cos%5E2%28a%29 ALIGN=MIDDLE  ALT=\"sin%5E2%28a%29=1-cos%5E2%28a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.........substitute <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos%28a%29=-4%2F5 ALIGN=MIDDLE  ALT=\"cos%28a%29=-4%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%5E2%28a%29=1-%28-4%2F5%29%5E2 ALIGN=MIDDLE  ALT=\"sin%5E2%28a%29=1-%28-4%2F5%29%5E2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%5E2%28a%29=1-%2816%2F25%29 ALIGN=MIDDLE  ALT=\"sin%5E2%28a%29=1-%2816%2F25%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%5E2%28a%29=25%2F25-16%2F25 ALIGN=MIDDLE  ALT=\"sin%5E2%28a%29=25%2F25-16%2F25\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%5E2%28a%29=9%2F25 ALIGN=MIDDLE  ALT=\"sin%5E2%28a%29=9%2F25\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%28a%29=sqrt%289%2F25%29 ALIGN=MIDDLE  ALT=\"sin%28a%29=sqrt%289%2F25%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "then <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%28a%29+=+3%2F5 ALIGN=MIDDLE  ALT=\"sin%28a%29+=+3%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" > or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%28a%29+=-+3%2F5 ALIGN=MIDDLE  ALT=\"sin%28a%29+=-+3%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "use identity:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%282a%29=2+sin%28a%29+cos%28a%29+ ALIGN=MIDDLE  ALT=\"sin%282a%29=2+sin%28a%29+cos%28a%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" >..........substitute <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%28a%29 ALIGN=MIDDLE  ALT=\"sin%28a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >  and<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+cos%28a%29 ALIGN=MIDDLE  ALT=\"+cos%28a%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( " note: since <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a ALIGN=MIDDLE  ALT=\"a\"   DISABLED_style= \"max-width:90%; height:auto;\" > is in quadrant <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=II ALIGN=MIDDLE  ALT=\"II\"   DISABLED_style= \"max-width:90%; height:auto;\" >, the info leads to<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+sin%28a%29+=++3%2F5 ALIGN=MIDDLE  ALT=\"+sin%28a%29+=++3%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" >,so  we have\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%282a%29=2+%283%2F5%29%28-4%2F5%29 ALIGN=MIDDLE  ALT=\"sin%282a%29=2+%283%2F5%29%28-4%2F5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sin%282a%29=-24%2F25 ALIGN=MIDDLE  ALT=\"sin%282a%29=-24%2F25\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( " </SPAN>\n" );
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