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MathsMediumMCQ2023 · 25 Jan Shift 1

Q80.Let x = 2 be a local minima of the function f(x) = 2x4 −18x2 + 8x + 12, x ∈(−4, 4). If M is local maximum value of the function f in (−4, 4), then M = (1) 12√6 −332 (2) 12√6 −312 (3) 18√6 −332 (4) 18√6 −312

What This Question Tests

The question requires finding local maximum and minimum values of a polynomial function within a given interval using the first derivative test and evaluating the function at critical points.

Concepts Tested

First derivative test for local extremaSecond derivative testFinding critical pointsEvaluating function at critical points and endpoints

Formulas Used

f'(x) = 0 for critical points

Sign change of f'(x) for local extrema

📚 NCERT Sections This Tests

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