document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1180320>Question 1180320</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If sin α = 4/5 and cos β = -5/13 for α in Quadrant I and β in Quadrant II, find cos(α - β) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #809944 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13203)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=809944\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "sin α = 4/5 in quadrant I means cos α = 3/5.<br><BR>\n" );
document.write( "cos β = -5/13 in quadrant II means sin β = 12/13.<br><BR>\n" );
document.write( "Then cos(A-B)=cos(A)cos(B)-sin(A)sin(B)<br><BR>\n" );
document.write( "Easy calculations....<br><BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );