Question 10 • Precalculus
The midpoint of endpoints z₁ and z₂ is (z₁ + z₂)/2, so you add the endpoints and multiply by 1/2. Subtracting the endpoints and dividing by 2 gives half the difference, not the midpoint in general. For conjugates a + bi and a − bi, their midpoint is a, which lies on the x-axis.
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