document.write( "Question 774384: find th values for which the rational expression is undefined -6+9x/x^3-8x^2+7 \n" ); document.write( "
Algebra.Com's Answer #472215 by lwsshak3(11628)\"\" \"About 
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find the values for which the rational expression is undefined -6+9x/x^3-8x^2+7
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\n" ); document.write( "expression is undefined if denominator=0
\n" ); document.write( "x^3-8x^2+7=0
\n" ); document.write( "solve for x using rational roots theorem:\r
\n" ); document.write( "\n" ); document.write( "....0...|.....1.......-8........0.........7.....
\n" ); document.write( "....1...|.....1.......-7......-7.......-7 (1 is a root)
\n" ); document.write( "(x-1)(x^2-7x-7)
\n" ); document.write( "x^2-7x-7=0
\n" ); document.write( "solve by quadratic formula:
\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"
\n" ); document.write( "a=1, b=-7, c=-7
\n" ); document.write( "x≈0.8875
\n" ); document.write( "or
\n" ); document.write( "x=7.8875
\n" ); document.write( "expression is undefined if: x=1, 0.8875, or 7.885
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