document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=845900>Question 845900</A>: <I><SPAN STYLE=\"word-break: break-all;\"> let cos A = -5/13 with A in Q2 and sin B= 3/5 with B in Q1\r<BR>\n" );
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document.write( "Find 1. CSC(A-B) 2. TAN(A+B) 3. SEC(A+B) 4. In what Q does (A+B) terminate? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #510258 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=510258\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let cos A = -5/13 with A in Q2 and sin B= 3/5 with B in Q1 <BR>\n" );
document.write( "Find 1. CSC(A-B) 2. TAN(A+B) 3. SEC(A+B) 4. In what Q does (A+B) terminate?<BR>\n" );
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document.write( "cos A=-5/13<BR>\n" );
document.write( "sin A=12/13<BR>\n" );
document.write( "..<BR>\n" );
document.write( "sin B=3/5<BR>\n" );
document.write( "cos B=4/5<BR>\n" );
document.write( "..<BR>\n" );
document.write( "1. csc (A-B)=1/sin(A-B)<BR>\n" );
document.write( "sin(A-B)=sin A*cos B-cos A*sinB=12/13*4/5(-(-5/13)*3/5)=48/65+15/65=63/65<BR>\n" );
document.write( "csc(A-B)=65/63<BR>\n" );
document.write( "..<BR>\n" );
document.write( "3.sec (A+B)=1/cos(A+B)<BR>\n" );
document.write( "cos(A+B)=cos A*cos B+sin A*sinB=-5/13*4/5-12/13*3/5)=-20/65-36/65=-56/65<BR>\n" );
document.write( "sec(A+B)=-65/56<BR>\n" );
document.write( "..<BR>\n" );
document.write( "2. tan(A+B)=sin(A+B)/cos(A+B)<BR>\n" );
document.write( "sin(A+B)=sin A*cos B+cos A*sinB=12/13*4/5+(-5/13)*3/5)=48/65-15/65=33/65<BR>\n" );
document.write( "tan(A+B)=-33/56<BR>\n" );
document.write( "..<BR>\n" );
document.write( "4. cos A=-5/13 (in Q2)<BR>\n" );
document.write( "A&#8776;112.62<BR>\n" );
document.write( "sin B=3/5<BR>\n" );
document.write( "B&#8776;36.87&#730;<BR>\n" );
document.write( "A+B&#8776;149.49&#730;<BR>\n" );
document.write( "A+B terminates in quadrant II<BR>\n" );
document.write( "..<BR>\n" );
document.write( "A-B&#8776;75.75<BR>\n" );
document.write( "calculator check:<BR>\n" );
document.write( "sin(A-B)&#8776;sin(75.75)&#8776;0.9692<BR>\n" );
document.write( "exact value=63/65&#8776;0.9692<BR>\n" );
document.write( "..<BR>\n" );
document.write( "sin(A+B)&#8776;sin(149.49)&#8776;0.5077<BR>\n" );
document.write( "exact value=33/65&#8776;0.5077<BR>\n" );
document.write( "..<BR>\n" );
document.write( "cos(A+B)&#8776;cos(149.49)&#8776;-0.8615<BR>\n" );
document.write( "exact value=-56/65&#8776;-0.8615<BR>\n" );
document.write( "..<BR>\n" );
document.write( "tan(A+B)=tan(149.49)=-0.5892<BR>\n" );
document.write( "exact value=-33/56&#8776;-0.5892<BR>\n" );
document.write( " </SPAN>\n" );
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