document.write( "Question 1087116: f is define as follows: f(x)=x(x+1) solve the inequality f(x) >6 \n" ); document.write( "

Algebra.Com's Answer #701408 by ikleyn(52780) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "x*(x+1) > 6   is equivalent to  \r\n" );
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document.write( " > 6   is equivalent to\r\n" );
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document.write( " > 0   is equivalent to\r\n" );
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document.write( "(x+3)*(x-2) > 0.\r\n" );
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document.write( "The last inequality has two sets of solutions:  1)  x < -3,   and  2)  x > 2.\r\n" );
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document.write( "In the interval form: (,-3) U (2,).\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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\n" ); document.write( "\n" ); document.write( "Illustration:\r
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\n" ); document.write( "\n" ); document.write( "Plot y = x*(x+1) (red line) and y = 6 (green line)\r
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\n" ); document.write( "The solution by @josgarithmetic is WRONG. For your safety, ignore it !\r
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