document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=562193>Question 562193</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find all values of x in the interval [0, 2&#960;] that satisfy the equation. \r<BR>\n" );
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document.write( "16 + 8 cos(2x) = 24 cos(x) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #364927 by </B><A HREF=/tutors/aboutme.mpl?userid=lwsshak3><B>lwsshak3(11628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lwsshak3><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=364927\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Find all values of x in the interval [0, 2&#960;] that satisfy the equation. <BR>\n" );
document.write( "16 + 8 cos(2x) = 24 cos(x)<BR>\n" );
document.write( "divide by 8<BR>\n" );
document.write( "2 + cos(2x) = 3 cos(x)<BR>\n" );
document.write( "2 + cos^2(x)-sin^2(x) = 3 cos(x)<BR>\n" );
document.write( "2 + cos^2(x)-1+cos^2(x) = 3 cos(x)<BR>\n" );
document.write( "2cos^2(x)-3cos(x)+1=0<BR>\n" );
document.write( "(2cos(x)-1)(cos(x)-1)=0<BR>\n" );
document.write( "..<BR>\n" );
document.write( "2cosx-1)=0<BR>\n" );
document.write( "cosx=1/2<BR>\n" );
document.write( "x=&#960;/3 and 5&#960;/3 (quadrants I and IV where cos>0)<BR>\n" );
document.write( "or<BR>\n" );
document.write( "(cos(x)-1)=0<BR>\n" );
document.write( "cosx=1<BR>\n" );
document.write( "x=0 </SPAN>\n" );
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