Algebramedium · Past Paper
If x^2 + 1/x = 0, which is not true?
Ax^3 + 1 = 0
Bx is a complex number
Cx = -1
Dx = 1
✓ Correct Answer: D — x = 1
x^2 + 1/x = 0 implies (x^3 + 1)/x = 0, so x^3 = -1, x = -1. Thus x=1 is false.
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