For how many real values of x is the equation x² + 4 = 0 true?
A0
B1
C2
DInfinitely many
Answer & Solution
Correct answer: A. 0
x² ≥ 0 for all real x, so x² + 4 ≥ 4. Therefore x² + 4 cannot equal 0 for any real x. ZERO real solutions. (Complex solutions exist: x = ±2i — but those aren't real.)
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