document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=694809>Question 694809</A>: <I><SPAN STYLE=\"word-break: break-all;\"> cos[ sin^-1 (-5/13)- cos^-1 (12/13] </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #428215 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=428215\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> cos[ sin^-1 (-5/13)- cos^-1 (12/13]<BR>\n" );
document.write( "---<BR>\n" );
document.write( "Assume A is in QIII<BR>\n" );
document.write( "Let A = sin^-1(-5/13), then cos(A) = -12/13<BR>\n" );
document.write( "----<BR>\n" );
document.write( "Assume B is in QI<BR>\n" );
document.write( "Let B = cos^-1)(12/13), then sin(B) = 5/13<BR>\n" );
document.write( "----<BR>\n" );
document.write( "Your Problem:<BR>\n" );
document.write( "cos[A + B] = cos(A)(cos(B))- sin(A)(sin(B)<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "= (-12/13)(12/13) - (-5/13)(5/13)<BR>\n" );
document.write( "---<BR>\n" );
document.write( "= (-144 + 25)/13^2<BR>\n" );
document.write( "-----<BR>\n" );
document.write( "= -0.7041<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" );