document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1001389>Question 1001389</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find cos (s+t) and cos (s-t)\r<BR>\n" );
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document.write( "Cos(s)= 1/5  and  sin(t)= 3/5\r<BR>\n" );
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document.write( "s and t in Quadrant I\r<BR>\n" );
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document.write( "cos(s+t)=?\r<BR>\n" );
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document.write( "Simplify your answer, including any radicals. Use integers or fractions for any numbers in the expression. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #618628 by </B><A HREF=/tutors/aboutme.mpl?userid=Cromlix><B>Cromlix(4381)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Cromlix><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=Cromlix><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=618628\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Hi there,<BR>\n" );
document.write( "If Cos(s) = 1/5 Sin(s) = root24/5<BR>\n" );
document.write( "If Sin(t) = 3/5 Cos(t) = 4/5<BR>\n" );
document.write( "Cos(s + t) = coss cost-sins sint<BR>\n" );
document.write( "Cos(s + t) = 1/5*4/5 - root24/5*3/5<BR>\n" );
document.write( "Cos(s + t) = (4 - 6 root6)/25<BR>\n" );
document.write( "........................<BR>\n" );
document.write( "Cos(s - t) = coss cost+sins sint<BR>\n" );
document.write( "Cos(s - t) = 1/5*4/5 + root24/5*3/5<BR>\n" );
document.write( "Cos(s - t) = (4 + 6 root6)/25<BR>\n" );
document.write( "...........................<BR>\n" );
document.write( "Hope this helps :-) </SPAN>\n" );
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