document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=181070>Question 181070</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Show how both sides equal.<BR>\n" );
document.write( "2 cos^2 30 degrees-1 = cos 60 degrees </SPAN>\n" );
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document.write( "cos30= sqr(3)/2<BR>\n" );
document.write( "cos60= 1/2\r<BR>\n" );
document.write( "\n" );
document.write( "2cos^2(30) - 1 = cos60<BR>\n" );
document.write( "2(cos30)^2 -1 <BR>\n" );
document.write( "2(sqr(3)/2)^2 -1<BR>\n" );
document.write( "2(3/4) -1 <BR>\n" );
document.write( "3/2 -1<BR>\n" );
document.write( "1/2<BR>\n" );
document.write( "1/2 = cos60<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );