What is the value of p ?

For the next two (02) items that follow : x^4 + px^3 + qx^2 + x + 6 is divisible by x^2 - x - 6.

  1. A. -2
  2. B. -1
  3. C. 1
  4. D. 2

Correct Answer: B. -1

Explanation

Since x^2 - x - 6 = (x-3)(x+2), the polynomial must yield 0 when x=3 and x=-2. Substituting x=3 gives 27p + 9q = -90 \implies 3p + q = -10. Substituting x=-2 gives -8p + 4q = -20 \implies 2p - q = 5. Adding the equations yields 5p = -5 \implies p = -1.

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