SOLUTION: What does my teacher want me to do when she puts this item on my study guide? "p/q where p & q are integers"

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Question 394166: What does my teacher want me to do when she puts this item on my study guide?
"p/q where p & q are integers"
Found 2 solutions by Alan3354, stanbon:
Answer by Alan3354(69443) About Me  (Show Source):
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
What does my teacher want me to do when she puts this item on my study guide?
"p/q where p & q are integers"
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It might be best to ask your teacher.
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If you have a polynomial of the form
ax^n+bx^(n-1)+...+x+z = 0
the rational roots will have the
form p/q where p is an integer divisor
of z and p is an integer divisor
of a.
---
Example
If 3x^3+2x^2+x+2=0 has rational roots
the roots are of the form p/q where
p = +-1 or +-2
and
q = +-1 or +-3
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So the rational numbers you would test
would be +-1,+-2,+-1/3,+-2/3
---
If none of those are rational roots the
cubic has no rational roots.
By the way, a cubic MUST have at least
one rational root.
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Cheers,
Stan H.