How do you find the centroid of the region bounded by the curves y = x^3, y = x, y = 2, and y = 0?

Finding the Centroid of Bounded Curves

To find the centroid (center of mass) of the region bounded by the curves:

  • y = x3
  • y = x
  • y = 2
  • y = 0

We can follow these steps:

Step 1: Determine the Points of Intersection

First, we need to find the intersection points of the curves:

  • Set y = x and y = x3:

    x = x3

    x3 – x = 0

    x(x2 – 1) = 0

    x = 0, x = 1, and x = -1 (but we are interested only in the region of interest where y is positive).
  • Set y = x and y = 2:

    x = 2

So, the points of intersection that define the region are at:

  • (0, 0)
  • (1, 1)
  • (2, 2)

Step 2: Set Up the Integrals

To find the area of the region and the coordinates of the centroid (xc, yc), we use:

Area (A)

The area A can be found using:

		A = ∫[f(x) - g(x)] dx
		

where f(x) is the upper curve (y = 2) and g(x) is the lower curve (y = x3) in the interval from 0 to 1.

Centroid Coordinates

The coordinates of the centroid can be calculated using the formulas:

  • xc = (1/A) ∫ x(f(x) – g(x)) dx
  • yc = (1/A) ∫ (1/2)(f(x)2 – g(x)2) dx

Where the limits of integration will be defined based on the region from 0 to 2.

Step 3: Perform the Integration

 

1. First, calculate the area:

		A = ∫02(2 - 0) dx = 2 
	

2. Now calculate xc:

		xc = (1/A) ∫02x(2 - 0) dx 
		 = (1/2) ∫022x dx 
		 = (1/2)[x2]|02 
		 = 2/3 
	

3. Finally, calculate yc:

		yc = (1/A) ∫02(1/2)(4 - 0) dx = (1/2)(4) = 2 
	

Final Result

The coordinates of the centroid of the bounded region are:

  • xc = 2/3
  • yc = 2

Therefore, the centroid of the region bounded by the given curves is at the point (2/3, 2).

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