document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1120331>Question 1120331</A>: <I><SPAN STYLE=\"word-break: break-all;\"> prove that ( double angle formula)<BR>\n" );
document.write( "a) cos^2 2A = 4cos^4 A -4cos^2 A+1\r<BR>\n" );
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document.write( "can u plz me sloving this<BR>\n" );
document.write( "thx  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #736021 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=736021\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Factor the right side into (2 cos^2 A-1)^2<BR>\n" );
document.write( "Take the square root<BR>\n" );
document.write( "cos 2A=2 cos^2A-1 </SPAN>\n" );
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