Question
Find the largest rectangle (that is , the rectangle with largest area) that fits inside the graph of the parabola y=x^2 below the line y=a (a is an unspecified constant value), with the top side of the rectangle on the horizontal line y=a
Solution
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(173 Votos)
Yeda
Elite · Tutor por 8 anos
Resposta
To find the largest rectangle that fits inside the graph of the parabola
below the line
, we need to determine the dimensions of the rectangle that maximize its area.Let's denote the x-coordinate of the vertex of the parabola as
. The equation of the parabola is
, so the vertex is at
. The line
intersects the parabola at two points,
and
, where
and
are the x-coordinates of the points of intersection.The rectangle that fits inside the parabola and below the line
has its top side on the line
and its bottom side on the parabola
. The width of the rectangle is
, and the height is
.The area of the rectangle is given by the product of its width and height, which is:
To maximize the area, we need to find the values of
and
that maximize this expression. Taking the derivative of
with respect to
and setting it equal to zero, we get:
Solving this equation for
, we find:
Substituting this value back into the equation for
, we get:
Therefore, the dimensions of the largest rectangle that fits inside the graph of the parabola
below the line
are:Width:
Height:
The maximum area of the rectangle is: