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MathsMediumMCQ2010 · Unknown

Q81.Let f : R →R be defined by f(x) = {k2x−2x,+ 3, ifif xx ≤−1> −1 possible value of k is (1) 0 (2) −12 (3) −1 (4) 1

What This Question Tests

This question tests the understanding of continuity for piecewise functions and the conditions for a local extremum. Ensuring continuity at the critical point x=-1 leads to k=-1, but this value results in a local maximum rather than a local minimum, indicating a potential discrepancy in the problem statement, but k=-1 is the only value that ensures continuity.

Concepts Tested

Continuity of piecewise functionsLocal maxima and minimaFirst derivative test

Formulas Used

Conditions for continuity at a point

First derivative test for extrema

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