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प्रश्न
Write the negation of the following statements :
(a) Chetan has black hair and blue eyes.
(b) ∃ x ∈ R such that x2 + 3 > 0.
उत्तर
(a) Chetan has no black hair or no blue eyes.
(b) ∀ x ∈ R such that x2 + 3 ≤ 0.
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