document.write( "Question 1029560: √3*sin(x/2)+cos(x/2)=0\r
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Algebra.Com's Answer #644567 by ikleyn(52798)\"\" \"About 
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document.write( "\"sqrt%283%29%2Asin%28x%2F2%29+%2B+cos%28x%2F2%29\" = \"0\"  --->  (divide bith sides by 2)  ---> \r\n" );
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document.write( "\"%28sqrt%283%29%2F2%29%2Asin%28x%2F2%29+%2B+%281%2F2%29%2Acos%28x%2F2%29\" = \"0\".   (1)\r\n" );
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document.write( "Notice that \"sqrt%283%29%2F2\" = \"cos%28pi%2F6%29\"  and  \"1%2F2\" = \"sin%28pi%2F6%29\".\r\n" );
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document.write( "Therefore, you can rewrite (1) as\r\n" );
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document.write( "\"cos%28pi%2F6%29%2Asin%28x%2F2%29+%2B+sin%28pi%2F6%29%2Acos%28x%2F2%29\" = \"0\".   (2)\r\n" );
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document.write( "Now apply the addition formula for sine \"cos%28alpha%29%2Asin%28beta%29%2Bsin%28alpha%29%2Acos%28beta%29\" = \"sin%28alpha+%2B+beta%29\".\r\n" );
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document.write( "You will get instead of (2)\r\n" );
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document.write( "\"sin%28pi%2F6+%2B+x%2F2%29\" = \"0\".\r\n" );
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document.write( "Then  pi/6 + x/2 = \"k%2Api\",  k = 0, +/-1, +/-2, . . . \r\n" );
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document.write( "Hence x = \"2k%2Api+-+pi%2F3\".\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 = \"2pi+-+pi%2F3\" = \"5pi%2F3\"  and  x = \"4pi+-+pi%2F3\" = \"11pi%2F3\".\r\n" );
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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 = \"5pi%2F3\"  and x = \"11pi%2F3\".\r\n" );
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