document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1198384>Question 1198384</A>: <I><SPAN STYLE=\"word-break: break-all;\"> After transformations, the expression sin (A + B)sin (A - B) can be proved to be equal to:<BR>\n" );
document.write( "A) sin^2 A - sin^2 <BR>\n" );
document.write( "B) sin A - sin B  <BR>\n" );
document.write( "C) 2 sin A sin B<BR>\n" );
document.write( "D) 2 cos A cos B<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #831960 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52787)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=831960\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "After transformations, the expression sin (A + B)sin (A - B) can be proved to be equal to:<BR>\n" );
document.write( "A) sin^2 A - sin^2 <BR>\n" );
document.write( "B) sin A - sin B  <BR>\n" );
document.write( "C) 2 sin A sin B<BR>\n" );
document.write( "D) 2 cos A cos B<BR>\n" );
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document.write( "Your writing in (A) is fatally defective, making the entire problem damaged and unusable.\r<BR>\n" );
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document.write( "We can not guess what is hidden there (if any).\r<BR>\n" );
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document.write( "<U>Comment from student</U>: I agree with you. Can not be solved with the information given. <BR>\n" );
document.write( "The problem writer must be out of his mind. Only by wild guessing, and then. Thanks anyway.\r<BR>\n" );
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document.write( "<U>My response</U> : very' sound judgment - a rarity in this forum.\r<BR>\n" );
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