Question

Algum gênio para me ajudar a resolver:

Answer 1

A massa será dada pelo integral duplo:

$\displaystyle M = \iint\limits_A \delta(x,y) \textrm{ d}x \textrm{ d}y = \int\limits_0^2 \left(\int\limits_x^{4x} x \textrm{ d}y \right)\textrm{ d}x = \int\limits_0^2 x\left[y\right]_{y=x}^{y=4x}\textrm{ d}x = \int\limits_0^2 3x^2\textrm{ d}x =$

$\displaystyle =\left[x^3\right]_{x=0}^{x=2} = 8.$