document.write( "Question 971803: For the equation
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Algebra.Com's Answer #854514 by ikleyn(53909) $\"\"$ $\"About$

You can put this solution on YOUR website!
.
\n" ); document.write( "For the equation
\n" ); document.write( "cos(5 x) = −1
\n" ); document.write( "find the smallest solution, the largest solution and the number of solutions for x in the interval 0 ≤ x ≤ 2π.
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\n" ); document.write( "\n" ); document.write( "        Regarding this problem, I'd like to make two comments.\r
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\n" ); document.write( "\n" ); document.write( "        First, in Math text, a professional Math writer would never write for such problem   0 <= x <= 2π.\r
\n" ); document.write( "\n" ); document.write( "        A professional writer will write   0 <= x < 2π. Find the difference.\r
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\n" ); document.write( "\n" ); document.write( "        Second, the solution and the answer in the post by @lwsshak3 are incorrect.\r
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\n" ); document.write( "\n" ); document.write( "        For correct solution, see my post below.\r
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document.write( "cos(5x) = -1\r\n" );
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document.write( "5x = π, 3π, 5π, 7π, 9π, . . . \r\n" );
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document.write( "x = , ,   = π,   ,  , . . . \r\n" );
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document.write( "For greater or smaller values of 5x,  values of x will be out of the given interval.\r\n" );
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document.write( "So, there are 5 solutions to the given equation in interval 0 <= x < 2π.\r\n" );
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document.write( "The smallest is  .  The greatest is  .  The number of solutions is 5.    ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved correctly.\r
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\n" ); document.write( "\n" ); document.write( "I am surprising to see so elementary error in the post by @lwsshak3.\r
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