document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=682705>Question 682705</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Use a half-angle formula to find the exact value of sin ((3pi)/8) \r<BR>\n" );
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document.write( "Thanks!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #423611 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=423611\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Use a half-angle formula to find the exact value of sin ((3pi)/8) <BR>\n" );
document.write( "Identity:sin(s/2)=±&#8730;[(1-cos s)/2]<BR>\n" );
document.write( "sin(3&#960;/8)=sin[(3&#960;/4)/2]=&#8730;[1-cos(3&#960;/4)/2]=&#8730;[1-(-&#8730;2/2)/2]=&#8730;[(1+&#8730;2/2)/2]<BR>\n" );
document.write( "sin(3&#960;/8)=&#8730;[(1+&#8730;2/2)/2]<BR>\n" );
document.write( "check with calculator:<BR>\n" );
document.write( "sin(3&#960;/8)&#8776;.9238..<BR>\n" );
document.write( "&#8730;[(1+&#8730;2/2)/2]&#8776;.9238.. </SPAN>\n" );
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