document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=206780>Question 206780</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Simplfy: cos((3*)/4+x)+ sin((3*)/4-x)<BR>\n" );
document.write( "Note: * = pie </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #156372 by </B><A HREF=/tutors/aboutme.mpl?userid=RAY100><B>RAY100(1637)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=RAY100><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=156372\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> cos{ (3pi/4) +x} +sin { (3pi/4) -x}<BR>\n" );
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document.write( "The  ref  angle  for  (3pi/4) = pi/4<BR>\n" );
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document.write( "cos { (3pi/4 +x} = -cos (pi/4 -x),,,as  long  as  x<pi/4<BR>\n" );
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document.write( "sin { (3pi/4)-x} = sin (pi/4 +x)<BR>\n" );
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document.write( "-cos (pi/4-x) + sin(pi/4 +x)<BR>\n" );
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document.write( "sin(pi/4 +x) - cos(pi/4-x)<BR>\n" );
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document.write( " Discussion: it  is  tempting  to  use  the  \"sum  and  difference  identities\"<BR>\n" );
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document.write( "but  this  does  not  appear  to  \"simplify\"<BR>\n" );
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document.write( "Realizing  that  (pi/4) is  45  degrees,  this  is  not  a  bad  simplification<BR>\n" );
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