document.write( "Question 469720: i dont understand how to put this in interval notation. (x^2+2x-8/x+1) less than or equal to 0.
\n" ); document.write( "i get to x=-4 x=2 x=-1 just need help putting it in interval notation. thanks! \n" ); document.write( "

Algebra.Com's Answer #322243 by ccs2011(207) $\"\"$ $\"About$

You can put this solution on YOUR website!
Ok first off notice when x = -1, the function becomes undefined
\n" ); document.write( "So when stating the domain, do not include x = -1.
\n" ); document.write( "Yes you have correctly identified the zeroes, x=-4 and x = 2.
\n" ); document.write( "But when is the function less than zero.
\n" ); document.write( " $\"%28%28x%2B4%29%28x-2%29%29%2F%28x%2B1%29+%3C+0\"$
\n" ); document.write( "There are 3 factors to consider:
\n" ); document.write( "x+4 < 0 --> x < -4
\n" ); document.write( "x-2 < 0 --> x < 2
\n" ); document.write( "x+1 < 0 --> x < -1
\n" ); document.write( "**Note: Multiplying/Dividing 2 negative numbers equal a positive number**
\n" ); document.write( "When x < -4, it satisfies all 3 conditions making each factor negative thus making the entire expression negative
\n" ); document.write( "When -4 < x < -1, it satisfies 2 conditions making 2 factors negative thus making entire expression positive
\n" ); document.write( "When -1 < x < 2, it satisfies 1 condition making 1 factor negative thus making entire expression negative
\n" ); document.write( "When x > 2, all factors are positive thus expression is positive
\n" ); document.write( "Therefore, expression is less than or equal to zero when x <= -4 and -1 < x <= 2
\n" ); document.write( "In interval notation, use brackets and parenthesis instead of \"<\" symbols
\n" ); document.write( "Domain: ( $\"-+infinity\"$ ,-4]U(-1,2]
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