GATE 2024 ST – Question 47
Continuous f:[−2,2]→ℝ satisfies which statements?
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Show answer and explanation
Correct answer: (A) F(x)=∫₀ˣf(t)dt on [0,2] is differentiable on (0,2).; (B) For any ten points x₁,…,x₁₀ there is x₀ with f(x₀)=[Σf(x_i)]/10.; (C) f is bounded on [−2,2].
Explanation
A follows from the fundamental theorem of calculus. The average in B lies between the minimum and maximum of continuous f, so the intermediate value theorem gives x₀. Compactness gives boundedness C. For D each term f(x/k)/x→f′(0)/k, giving the harmonic sum (1+1/2+⋯+1/10)f′(0), not generally 10f′(0). **A,B,C**.