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If \(a_1, a_2, ..., a_8\) are the roots of the equation \(x^8 + x^7 + ... + x + 1 = 0\), then the value of \(a_1^{2025} + a_2^{2025} + ... + a_8^{2025}\) is

Question and options

If a1,a2,...,a8a_1, a_2, ..., a_8 are the roots of the equation x8+x7+...+x+1=0x^8 + x^7 + ... + x + 1 = 0, then the value of a12025+a22025+...+a82025a_1^{2025} + a_2^{2025} + ... + a_8^{2025} is
  1. 0
  2. 2
  3. 8
  4. 4

Answer and explanation

Correct answer: C - 8
The roots are the 9th roots of unity other than 1, so a_i^9 = 1. Since 2025 = 9*225, each a_i^2025 = 1, and the sum is 8.

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