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MathsMediumMCQ2019 · 12 Jan Shift 1

Q82.The maximum area (in sq. units) of a rectangle having its base on the x− axis and its other two vertices on the parabola, y = 12 −x2 such that the rectangle lies inside the parabola, is : (1) 20√2 (2) 32 (3) 36 (4) 18√3

What This Question Tests

This question requires setting up an area function for the rectangle based on the parabola's equation, then finding its maximum value by using the first derivative test (setting the derivative to zero).

Concepts Tested

Area of a rectangleEquation of a parabolaOptimization using derivatives

Formulas Used

Area = length * width

d/dx(f(x))=0 for extremum

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