document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=820437>Question 820437</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In each case, find sin(a), cos(a), csc(a), sec(a), and cot(a). Note: 'a' means alpha.\r<BR>\n" );
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document.write( "45. cos(2a)=3/5 and 0°<2a<90°\r<BR>\n" );
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document.write( "I've been trying to figure out this problem for some time, but I need help. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #493546 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=493546\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In each case, find sin(a), cos(a), csc(a), sec(a), and cot(a). Note: 'a' means alpha.45. cos(2a)=3/5 and 0°<2a<90°<BR>\n" );
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document.write( "use cos half-angle formula:<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=cos%28s%2F2%29=sqrt%28%281%2Bcos%28s%29%29%2F2%29 ALIGN=MIDDLE  ALT=\"cos%28s%2F2%29=sqrt%28%281%2Bcos%28s%29%29%2F2%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=cos%282a%2F2%29=sqrt%28%281%2Bcos%282a%29%29%2F2%29=sqrt%28%281%2B%283%2F5%29%29%2F2%29%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sqrt%28%288%2F5%29%2F2%29=sqrt%28%288%2F10%29%29=sqrt%28%284%2F5%29%29 ALIGN=MIDDLE  ALT=\"sqrt%28%288%2F5%29%2F2%29=sqrt%28%288%2F10%29%29=sqrt%28%284%2F5%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >=2/&#8730;5=2&#8730;5/5<BR>\n" );
document.write( "sin(a)=&#8730;(1-cos^2(a))=&#8730;(1-4/5)=&#8730;(1/5)=1/&#8730;5=&#8730;5/5<BR>\n" );
document.write( "..<BR>\n" );
document.write( "sin(a)=&#8730;5/5<BR>\n" );
document.write( "csc(a)=&#8730;5<BR>\n" );
document.write( "cos(a)=2&#8730;5/5<BR>\n" );
document.write( "sec(a)=&#8730;5/2<BR>\n" );
document.write( "cot(a)=cos(a)/sin(a)=2/1=2<BR>\n" );
document.write( "..<BR>\n" );
document.write( "calculator check:<BR>\n" );
document.write( "cos(2a)=3/5<BR>\n" );
document.write( "2a&#8776;53.13&#730;<BR>\n" );
document.write( "a&#8776;26.565&#730;<BR>\n" );
document.write( "..<BR>\n" );
document.write( "sin(a)=sin(26.565)&#8776;0.4472..<BR>\n" );
document.write( "exact value as calculated=&#8730;5/5&#8776;0.4472..<BR>\n" );
document.write( "..<BR>\n" );
document.write( "cos(a)=cos(26.565)&#8776;0.8944..<BR>\n" );
document.write( "exact value as calculated=2&#8730;5/5&#8776;0.8944..\r<BR>\n" );
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