.
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document.write( "√3*sin(x/2)+cos(x/2)=0\r
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document.write( "(π≤x<4π)
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document.write( "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\r
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document.write( "
=
---> (divide bith sides by 2) ---> \r\n" );
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document.write( "
=
. (1)\r\n" );
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document.write( "Notice that
=
and
=
.\r\n" );
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document.write( "Therefore, you can rewrite (1) as\r\n" );
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document.write( "
=
. (2)\r\n" );
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document.write( "Now apply the addition formula for sine
=
.\r\n" );
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document.write( "You will get instead of (2)\r\n" );
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document.write( "
=
.\r\n" );
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document.write( "Then pi/6 + x/2 =
, k = 0, +/-1, +/-2, . . . \r\n" );
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document.write( "Hence x =
.\r\n" );
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document.write( "To get the given interval for x, take k = 1 and k = 2.\r\n" );
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document.write( "You will have two solutions x =
=
and x =
=
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document.write( "Answer. There are two solutions in the given interval. \r\n" );
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document.write( " They are x =
and x =
.\r\n" );
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