document.write( "Question 656250: Determine the value(s) of the variable that must be excluded from the domain.
\n" ); document.write( "f(x) = $\"x%5E2+-+16%29%2F%28-9x%5E2+%2B+27x+%2B+36%29\"$ \r
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Algebra.Com's Answer #409426 by Edwin McCravy(20060) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "The denominator must not be 0\r\n" );
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document.write( "-9x² + 27x + 36 ≠ 0\r\n" );
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document.write( "-9(x² - 3x - 4) ≠ 0\r\n" );
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document.write( "   -9(x-4)(x+1) ≠ 0\r\n" );
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document.write( "   x - 4 ≠ 0;  x + 1 ≠ 0\r\n" );
document.write( "       x ≠ 4;      x ≠ -1\r\n" );
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document.write( " The graph looks like this:\r\n" );
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document.write( "There is no point where x=-1 because there is a vertical \r\n" );
document.write( "asymptote there, and there is a hole in the curve, and\r\n" );
document.write( "therefore no point at (4,-), where the little circle is.\r\n" );
document.write( "So -1 and 4 are excluded from the domain.\r\n" );
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document.write( "The domain is\r\n" );
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document.write( "(-,-1) U (-1,4) U (4,)\r\n" );
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document.write( "Edwin

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