document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=69515>Question 69515</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the exact value of cos^-1(cos(4pi/3)).\r<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 #49511 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=49511\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Find the exact value of cos^-1(cos(4pi/3)). <BR>\n" );
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document.write( "You would think the answer was 4pi/3, <BR>\n" );
document.write( "but the range of cos^-1 is [0,pi]<BR>\n" );
document.write( "The corresponding angle is 2pi/3.<BR>\n" );
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document.write( "I think you will find the angle is (2/3)pi or 120 degrees.<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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