document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=87034>Question 87034</A>: <I><SPAN STYLE=\"word-break: break-all;\"> please help me solve my homework: simplify: sin(90degrees+ x) sin ( 180 degrees +x) + cos ( 90 degrees + x) cos ( 180 degrees - x ). </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #63001 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=63001\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> simplify: sin(90degrees+ x) sin ( 180 degrees +x) + cos ( 90 degrees + x) cos ( 180 degrees - x ).<BR>\n" );
document.write( "------------<BR>\n" );
document.write( "There are several ways to work this problem; you might want to do it anothe way,<BR>\n" );
document.write( "but here goes:<BR>\n" );
document.write( "sin(90+x) = cosx<BR>\n" );
document.write( "sin(180+x) = -sinx<BR>\n" );
document.write( "cos(90+x) = -sinx<BR>\n" );
document.write( "cos(180-x) = -cosx<BR>\n" );
document.write( "--------------------<BR>\n" );
document.write( "Your Problem:<BR>\n" );
document.write( "cosx*(-sinx)+(-sinx)(-cosx)<BR>\n" );
document.write( "==0<BR>\n" );
document.write( "============<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );