document.write( "Question 1198604: Find all values of x that satisfy the equation 2cosx-1=0, in the interval [0, 2pi]\r
\n" ); document.write( "\n" ); document.write( "The correct answer is one of the following.
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\n" ); document.write( "\n" ); document.write( "A) pi/2, 3pi/2\r
\n" ); document.write( "\n" ); document.write( "B) pi/4, 3pi/4\r
\n" ); document.write( "\n" ); document.write( "C) pi/2, 3pi/4\r
\n" ); document.write( "\n" ); document.write( "D) pi/6, 5pi/6\r
\n" ); document.write( "\n" ); document.write( "E) pi/3, 5pi/3 \n" ); document.write( "

Algebra.Com's Answer #832216 by ikleyn(52781) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "The given equation  2*cos(x) - 1 = 0 is equivalent to \r\n" );
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document.write( "    2*cos(x) = 1,  or  cos(x) = ,\r\n" );
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document.write( "which has the roots  x =   and  x =   in the interval [0,) and has no other roots in this interval. \r\n" );
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document.write( "ANSWER.  Option E).\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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\n" ); document.write( "\n" ); document.write( "By the way, interval [ $\"0\"$ , $\"2pi\"$ ] is shown INCORRECTLY in your post.\r
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\n" ); document.write( "\n" ); document.write( "The standard and traditional notation for this interval is [ $\"0\"$ , $\"2pi\"$ )\r
\n" ); document.write( "\n" ); document.write( " with the curved closing parenthesis.\r
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\n" ); document.write( "\n" ); document.write( "As you write it incorrectly, I can make my conclusion about your mathematical competency.\r
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