document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=428020>Question 428020</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How to simplify (1 + cos theta) (1 - cos theta) ? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #297570 by </B><A HREF=/tutors/aboutme.mpl?userid=John10><B>John10(297)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=John10><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=John10><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=297570\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> How to simplify (1 + cos theta) (1 - cos theta) ?\r<BR>\n" );
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document.write( "Use the formula a^2 - b^2 = (a-b)(a+b)\r<BR>\n" );
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document.write( "(1 + cos theta) (1 - cos theta) \r<BR>\n" );
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document.write( "= (1)^2 - (cos theta)^2 \r<BR>\n" );
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document.write( "= 1 - (cos theta)^2 \r<BR>\n" );
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document.write( "= (sin theta)^2 [because (sin x)^2 + (cos x)^2 = 1]\r<BR>\n" );
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document.write( "Hope it helps!John10 </SPAN>\n" );
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