document.write( "Question 538594: How to find rational roots of:
\n" ); document.write( "x^3 + 5x^2 - x - 5
\n" ); document.write( "I want to know what's the method.
\n" ); document.write( "Thank you \n" ); document.write( "

Algebra.Com's Answer #353222 by KMST(5328) $\"\"$ $\"About$

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If there is a rational root to a polynomial with integer coefficients, the numerator will be a factor of the independent term (-5 in this case), and the denominator will be a factor of the leading coefficient (the invisible +1 multiplying x^3 in this case). So the rational roots will have 1 for a denominator (they are integers). The factors of 5 are 1, and 5, and could appear as roots with a positive or negative sign.
\n" ); document.write( "You could just try them.
\n" ); document.write( "In this case, this polynomial looks like a factor-by-grouping example:
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\n" ); document.write( "So it turns out that the 3 roots are all rational, and are -5, -1, and +1.
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