document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=236887>Question 236887</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find (2x) given that sin(x)=2/5 and x is in quadrant II. Give exact value for sin(2x) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #174243 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=174243\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Find (2x) given that sin(x)=2/5 and x is in quadrant II. Give exact value for sin(2x)<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos%28x%29+=+sqrt%281+-+sin%5E2%28x%29%29 ALIGN=MIDDLE  ALT=\"cos%28x%29+=+sqrt%281+-+sin%5E2%28x%29%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%28x%29+=+sqrt%2821%2F25%29 ALIGN=MIDDLE  ALT=\"cos%28x%29+=+sqrt%2821%2F25%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "sin(2x) = 2sin(x)cos(x)<BR>\n" );
document.write( "= 2*(2/5)*sqrt(21)/5<BR>\n" );
document.write( "= 4sqrt(21)/25<BR>\n" );
document.write( "cos(x) is negative in Q2, so use the - sqrt<BR>\n" );
document.write( "sin(2x) = -4sqrt(21)/25 </SPAN>\n" );
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