Just a General Question about Differential Elements

[nimble anchor]

Why is the differential element dV for volume equal to dx dy dz? If the volume of an object is v = x * y * z, then shouldn't dv = dx * yz + dy * xz + dz * xy? In the same vein, why can you treat the differential element dr for radius of a sphere as dx * dy * dz? When you differentiate out p = sqrt(x^2 + y^2 + z^2), you get pdp = xdx + ydy + zdz.,

[nimble anchor]

<@&286206848099549185> :)

[twilit cove]

1. It comes from Riemann sum to Riemann integral. A good explanation is a little more advanced than my skillset

[nimble anchor]

i was hoping for the good explanation