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mglebiv
Find the dimensions of the rectangle of maximum area with sides parallel to the coordinate axes that can be inscribed in the ellipse 4x^2 +16y^2 = 16. I am totally confused on this one, can someone explain what to do please?
The rectangle area will be 4xy (take x, y as the point in the first quadrant) so A= xy = sqrt(16-16y^2)*y and now u have something to differentiate.