SOLUTION: The roots of (x^3) + 2p(x^2) - px + 10 = 0 are integral and form an arithmetic sequence. What is the value of p?

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Question 1191255: The roots of (x^3) + 2p(x^2) - px + 10 = 0 are integral and form an arithmetic sequence. What is the value of p?
Found 2 solutions by ikleyn, greenestamps:
Answer by ikleyn(52790) About Me  (Show Source):
Answer by greenestamps(13200) About Me  (Show Source):
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The three roots are integers in arithmetic progression, and their product is -10. Quick trial and error shows the roots are -1, 2, and 5. The polynomial is

%28x%2B1%29%28x-2%29%28x-5%29=x%5E3-6x%5E2%2B3x-10

Equate the coefficients of that polynomial and the polynomial in its given form to see that p = -3.

ANSWER: p = -3