Question

find the remaining zeros if -2 and -1 are the two zeros of:

f(x)= 2x^4 + x^3 - 14x^2 - 19x - 6

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Answer 1

Answer:

f (-2) = 2 × (-2)^4 + (-2)^3 - 14 × (-2)^2 - 19 × (-2) - 6

= 2 × 16 + (-8) - 14 × 4 + 38 - 6

= 32 - 8 -56 + 38 - 6

= 70 - 70

= 0

f(-1) = 2 × (-1)^4 + (-1)^3 - 14 × (-1)^2 - 19 × (-1) - 6

= 2 × 1 + (-1) - 14 × 1 + 19 -6

= 2 - 1 - 14 + 19 - 6

= 21 - 21

= 0