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Solve the equation. z⁶ -1=0

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Final answer:

The equation z⁶ - 1 = 0 factors into (z - 1)(z² + z + 1)(z + 1)(z² - z + 1) = 0. Solving each factor yields two real solutions, z = 1 and z = -1, and four complex solutions from the quadratic factors using the quadratic formula.

Step-by-step explanation:

The equation z⁶ - 1 = 0 can be solved by recognizing it as a difference of squares where z³ is squared. This equation factors into (z³ - 1)(z³ + 1) = 0, which further factors into (z - 1)(z² + z + 1)(z + 1)(z² - z + 1) = 0, using the sum and difference of cubes formulas.

Solving each factor for z gives us:

  • z = 1
  • z² + z + 1 = 0
  • z = -1
  • z² - z + 1 = 0

For the quadratic factors, we can use the quadratic formula to find complex solutions: z = (-b ± √(b² - 4ac)) / (2a), leading to two complex solutions for each quadratic factor.

Therefore, the solutions for z⁶ - 1 = 0 are z = 1, z = -1, and four complex numbers which are roots of the quadratic factors.

User John Doucette
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