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Find the dimension of the rectangle of largest area that has its base on the x-axis and its other two vertices above the x-axis and lying on the parabola.

a) 1 unit
b) 2 units
c) 3 units
d) 4 units

User Pewh Gosh
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1 Answer

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Final answer:

To find the dimensions of the rectangle of largest area, we need to consider the parabola and the x-axis. The dimensions are determined by the x-coordinate and the y-coordinate of the two vertices above the x-axis. By finding the maximum value of the area formula, we can determine the dimension of the rectangle of largest area.

Step-by-step explanation:

To find the dimensions of the rectangle of largest area, we need to consider the parabola and the x-axis. Let's assume the coordinates of the two vertices above the x-axis are (x, y) and (-x, y), where y is the value of the parabola at x.

The area of a rectangle is given by length x width. In this case, the length is 2x (twice the x-coordinate) and the width is y (the y-coordinate).

Therefore, the area of the rectangle is A = 2x * y.

To maximize the area, we need to find the maximum value of A. This can be done by finding the maximum value of y for a given x.

Since the other two vertices lie on the parabola, we have y = x^2. Substituting this into the area formula, we get A = 2x * x^2 = 2x^3.

To find the maximum value of A, we can take the derivative of A with respect to x and set it equal to 0. Taking the derivative, we get dA/dx = 6x^2.

Setting this equal to 0, we find x = 0 or x = ±√(3/2).

Since we want the dimension of the rectangle, we take the positive value of x, which is √(3/2).

Therefore, the dimension of the rectangle of largest area is approximately 1.22 units.

User Fan Ouyang
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