Solve the equation .

Answer and explanation

Correct answer: A.

  1. Step 1: By the quadratic formula, . Step 2. , so . **Answer: . Why not the others:** : That does not take the square root of the discriminant correctly. : The real part has the wrong sign. : That omits the ; the roots are not real.

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Solve the equation z 2 - 2z + 65 = 0. | Singapore GCE A-Level