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Find the value of p(-1) if p(x) = 7x⁵ + 6x⁴ + 4x³ + 5x² + 8x +9

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Answer:

p(-1) = 1

Explanation:

p(x) = 7x⁵ + 6x⁴ + 4x³ + 5x² + 8x +9

p(-1) = 7(-1)⁵ + 6(-1)⁴ + 4(-1)³ + 5(-1)² + 8(-1) +9

Note: (-1)^n will be positive 1 for all even values of n [e.g., (-1)^4 = 1] and negative 1 for all odd values of n [e.g., (-1)^3 = -1]

Therefore, we can write:

p(-1) = 7(-1) + 6(1) + 4(-1) + 5(1) + 8(-1) +9

p(-1) = -7 + 6 - 4 + 5 - 8 +9

p(-1) = 1

User Dimitris Maf
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