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MathsHardMCQ2024 · 30 Jan Shift 1

Q73.Let g : R →R be a non constant twice differentiable such that g′( 21 ) = g′( 23 ). If a real valued function f is defined as f(x) = 12 [ g(x) + g(2 −x)], then (1) f ′′(x) = 0 for atleast two x in (0, 2) (2) f ′′(x) = 0 for exactly one x in (0, 1) (3) f ′′(x) = 0 for no x in (0, 1) (4) f ′( 23 ) + f ′( 21 ) = 1

What This Question Tests

This question involves differentiating a symmetric function twice and then applying Rolle's Theorem or its concept to determine the number of roots of the second derivative.

Concepts Tested

DifferentiationSymmetric functionsRolle's Theorem / Intermediate Value Theorem for derivatives

Formulas Used

f'(x)

Rolle's Theorem (if f(a)=f(b), then f'(c)=0 for some c in (a,b))

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