document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=865985>Question 865985</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Question: Find all angles theta (I don't have a symbol for that) in radians on the interval [0,4pi] such that cos(theta) = 1/2.\r<BR>\n" );
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document.write( "I think I have to set a up graph from 0 to 4pi and draw a wavy line and determine at what points x crosses y=1/2. It that correct? How do I do that? </SPAN>\n" );
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document.write( "note that pi = 180 degrees, therefore the interval in degrees is [0, 720]<BR>\n" );
document.write( "the cosine of 60 degrees is 1/2<BR>\n" );
document.write( "we convert degrees to radians = degrees * pi/180<BR>\n" );
document.write( "60 degrees = pi/3 radians<BR>\n" );
document.write( "from the graph, we see the following<BR>\n" );
document.write( "the angles theta in radians are pi/3, 5*pi/3, 7*pi/3, 11*pi/3\r<BR>\n" );
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