document.write( "Question 1206253: Find all solutions in the interval [0,2pi)
\n" ); document.write( "4cos(theta)=1+2cos(theta) \n" ); document.write( "
Algebra.Com's Answer #843550 by Theo(13342)\"\" \"About 
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let x = theta.
\n" ); document.write( "equation is 4cos(x) = 1 + 2cos(x)
\n" ); document.write( "subtract 2cos(x) from both sides of the equation to get:
\n" ); document.write( "2cos(x) = 1
\n" ); document.write( "divide both sides of the equation by 2 to get:
\n" ); document.write( "cos(x) = 1/2
\n" ); document.write( "cosine is positive in quadrants 1 and 4.
\n" ); document.write( "in quadrant 1, x = arccos(1/2) = pi/3.
\n" ); document.write( "the equivalent angle in the fourth quadrant is 2pi - pi/3 = 5pi/3.
\n" ); document.write( "the graph of both equations is shown in below.
\n" ); document.write( "4cos(x) = 1 + 2cos(x) where the graph of both equations intersect in the interval (0,2pi).\r
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\n" ); document.write( "\n" ); document.write( "translating to degrees.
\n" ); document.write( "0 radians * 180/pi = 0 degrees.
\n" ); document.write( "2pi radians * 180/pi = 360 degrees.
\n" ); document.write( "pi/3 radians * 180/pi = 60 degrees.
\n" ); document.write( "5pi/3 radians * 180/pi = 300 degrees.\r
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