document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=793819>Question 793819</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If cos(t)=4/5, evaluate (i)cos(pi-t) and (ii)cos(t+pi) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #480449 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=480449\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If cos(t)=4/5, <BR>\n" );
document.write( "-----<BR>\n" );
document.write( "cos = x/r so x = 4 and r = 5<BR>\n" );
document.write( "The y = sqrt[5^2-4^2] = 3<BR>\n" );
document.write( "So, sin(t) = y/4 = 3/5<BR>\n" );
document.write( "===============================<BR>\n" );
document.write( "Evaluate <BR>\n" );
document.write( "(i)cos(pi-t) = cos(pi)*cos(t)+sin(pi)*sin(t)<BR>\n" );
document.write( "= (-1)*(4/5) + (3/5)*0<BR>\n" );
document.write( "= -4/5<BR>\n" );
document.write( "============================<BR>\n" );
document.write( " <BR>\n" );
document.write( "(ii)cos(t+pi) = cos(t)*cos(pi) - sin(t)*sin(pi)<BR>\n" );
document.write( "= (4/5)(-1) - (3/5)(0)<BR>\n" );
document.write( "= -4/5<BR>\n" );
document.write( "============================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( "============== </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );