What is the sum of the three complex cube roots of 8?
Answer and explanation
Correct answer: B. 0
- Step 1: The cube roots of 8 are the roots of z^3 - 8 = 0. Step 2. The z^2 coefficient is 0, so the sum of the roots is 0. Answer: 0. Why not the others: 2 is only the real root, 6 counts each root as 2, and 8 is the number whose roots are being found.
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