MHB What is the area between two intersecting parabolas?

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The area between the intersecting parabolas \(y = x^2\) and \(y = 2x - x^2\) is determined by their intersection points at \(x = 0\) and \(x = 1\). The area is calculated using the integral of the difference between the top function \(2x - x^2\) and the bottom function \(x^2\). The correct setup for the area is \(A = \int_0^1 (2x - x^2 - x^2) \, dx\), simplifying to \(A = 2\int_0^1 (x - x^2) \, dx\). The confusion regarding the negative area arises from not properly accounting for the functions' positions, ensuring the area is always positive. The final calculation will yield the correct area enclosed by the parabolas.
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Find the area of the region enclosed by the parabolas $$y = x^2 $$and $$y = 2x - x^2.$$

So they intersect at 0 and 1.

The derivative of $$y = 2x - x^2.$$ is $$\d{y}{x} = 2 - 2x$$

When I plug in 1 I get 0, and when I plug in 0, I get 2, so I subtract 2 from 0 and the area is -2. But the area should be positive, what am I doing wrong?
 
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The width of each area element is $dx$ and the height is the top function minus the bottom function, thus:

$$A=\int_0^1 \left(2x-x^2\right)-\left(x^2\right)\,dx=2\int_0^1 x-x^2\,dx$$

What do you get?
 

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