Let A = {n ∈ ℤ : n² ≤ 4} and B = {x ∈ ℝ : x² − 3x + 2 = 0}. Are A and B equal?
AYes, both equal {−2, −1, 0, 1, 2}
BYes, both equal {1, 2}
CNo — A = ∅; B = {1, 2}
DNo — A = {−2, −1, 0, 1, 2}; B = {1, 2}
Answer & Solution
Correct answer: D. No — A = {−2, −1, 0, 1, 2}; B = {1, 2}
A: integers with n² ≤ 4 → n ∈ {−2, −1, 0, 1, 2}. B: x² − 3x + 2 = (x − 1)(x − 2) = 0 → x = 1, 2 (both real). 0 ∈ A but 0 ∉ B, so A ≠ B.
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