MHB Finding Area Bounded by x^2 & 2x - x^2

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To find the area bounded by the curves y = x^2 and y = 2x - x^2, the intersection points are determined by setting x^2 equal to 2x - x^2, leading to the equation 2x - 2x^2 = 0, which factors to give x = 1. The area is calculated using the integral from 0 to 1 of the difference between the upper curve (2x - x^2) and the lower curve (x^2), expressed as ∫ from 0 to 1 of (2x - x^2 - x^2) dx. It's essential to confirm which function is on top by evaluating both at a point within the interval. A diagram is recommended for clarity in identifying the bounded area.
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Find the area bounded by the curves $$y = x^2[/math] and [math]y = 2x - x^2$$so
$$
x^2 = 2x - x^2$$
$$
2x - x^2 - x^2 = 2x - 2x^2$$

So then would I factor out a 2 and get
$$
2x(x - 1)$$
$$
x = 1$$

So the $$\int ^1_0 Right - left \, dx$$
 
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shamieh said:
Find the area bounded by the curves $$y = x^2[/math] and [math]y = 2x - x^2$$so
$$
x^2 = 2x - x^2$$
$$
2x - x^2 - x^2 = 2x - 2x^2$$

So then would I factor out a 2 and get
$$
2x(x - 1)$$
$$
x = 1$$

So the $$\int ^1_0 Right - left \, dx$$

The "Right" and "Left" is if you're doing an integral with respect to $y$. But you're integrating w.r.t. $x$. So it's what minus what?
 
Top - Bottom ?So would i get $$\int^1_0 x^2 - (2x -x ^2) dx$$
 
shamieh said:
Top - Bottom ?So would i get $$\int^1_0 x^2 - (2x -x ^2) dx$$

Yes, it is top minus bottom, but are you sure you have chosen correctly with regards to which is top and which is bottom? If you are unsure, pick an $x$-value inside the limits of integration and evaluate both functions to see which gives the greater value.
 
WORD OF GOD:

Always draw a diagram.
 

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