document.write( "Question 7537: For f(x)=1/x^2-2x-8 , find the interval(s) where f(x) < 0. \n" ); document.write( "
Algebra.Com's Answer #4168 by khwang(438)\"\" \"About 
You can put this solution on YOUR website!
At first, two big mistakes you did:
\n" ); document.write( " (I)wrong cateory posting
\n" ); document.write( " (II) missing parenthesis\r
\n" ); document.write( "\n" ); document.write( " Be careful!!!\r
\n" ); document.write( "\n" ); document.write( " f(x)=1/(x^2-2x-8) <0 is equivalent to x^2-2x-8 <0 [since 1 is positive.]\r
\n" ); document.write( "\n" ); document.write( " Solve x^2-2x-8 = (x - 4)(x+2) < 0.
\n" ); document.write( " [Note two roots 4 & -2 divide the whole real line ibnto 3 parts]\r
\n" ); document.write( "\n" ); document.write( " From the signs in diagram below:
\n" ); document.write( " + - +
\n" ); document.write( " ---------*--------*----------
\n" ); document.write( " -2 4
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\n" ); document.write( " The solution set : (-2, 4)\r
\n" ); document.write( "\n" ); document.write( " Here,I give you the simplest way to solve this kind of questions.
\n" ); document.write( " Try to read and think carefully about every step.
\n" ); document.write( " No further explanations will be given.\r
\n" ); document.write( "\n" ); document.write( " Kenny\r
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