Answer:
3x³ - 14x² - 7x + d = (x + 1)(ax² + bx + c)
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(x + 1)(ax² + bx + c)
= ax³ + bx² + cx + ax² + bx + c
= ax³ + (a + b)x² + (b + c)x + c
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ax³ + (a + b)x² + (b + c)x + c = 3x³ - 14x² - 7x + d
=> a = 3
a + b = -14
b + c = -7
c = d
=> a = 3, b = -17, c = 10, d = 10
