Q1. State whether the following statements are true or false. Justify your answers with a short proof or a counterexample
- i)) The negation of p V (~ q) is q → p. (100 words)
- ii)) Q\N is countable. (100 words)
- iii)) The equation x³ – 2x + 3 = 0 has a real root between -2 and 1. (100 words)
- iv)) Every increasing sequence has a convergent subsequence. (100 words)
- v)) The function defined as f(x) = { sin 2x / x, if x ≠ 0; 3, if x = 0 } has a removable discontinuity. (100 words)
- vi)) An integrable function can have finitely many points of discontinuity. (100 words)
- vii)) The series Σ(n=0 to ∞) (-1)^n / 2^n is divergent. (100 words)
- viii)) The function f defined by f(x) = sinx(1 + cosx), x ∈ [0, 2π], has local maximum at x = π/2. (100 words)
- ix)) Every constant function on [a, b] is Riemann Integrable. (100 words)
- x)) The function f : R → R defined by f(x) = |x − 2| + |x − 1| is differentiable at x = 3. (100 words)
- De Morgan's Laws are crucial for correct logical negation.
- Subsets of countable sets are always countable (e.g., `Q\N`).
- Intermediate Value Theorem guarantees a root for continuous functions with sign changes.
- Bolzano-Weierstrass Theorem requires a sequence to be *bounded* to ensure a convergent subsequence.
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