Find the mass of the rectangular region 0≤x≤1

, 0≤y≤2
with density function ρ(x,y)=2−y
.

1 answer

To find the mass of the rectangular region, we need to integrate the density function ρ(x,y) over the given region.

The mass M is given by the double integral of ρ(x,y) over the region:

M = ∬ ρ(x,y) dA

where dA represents an infinitesimal area element.

In this case, the rectangular region is defined by 0≤x≤1 and 0≤y≤2. Therefore, the mass M is given by:

M = ∫[0,1] ∫[0,2] (2-y) dy dx

We can integrate with respect to y first, from 0 to 2:

M = ∫[0,1] [(2y - (1/2)y^2)]|[0,2] dx

M = ∫[0,1] [(4 - 2)] dx

M = ∫[0,1] 2 dx

M = 2x |[0,1]

M = 2(1) - 2(0)

M = 2

So, the mass of the rectangular region 0≤x≤1, 0≤y≤2 with density function ρ(x,y)=2−y is 2.