I am using dS rather than dA because I still want to think of dA as maybe the area in one of the coordinate planes like the one we had in double integrals. You will see later where this comes in.

这里使用dS而不是dA，因为我习惯把dA看成是，坐标平面中的面积元，就像在二重积分中所做的那样，待会大家会了解。

youdao

So, for example, the area of region is the double integral of just dA, 1dA or if it helps you, one dA if you want.

举个例子，区域R的面积是dA的二重积分，便于理解，在这里写成。

youdao

Wayne, I know that you are not agree with Da-Shung Army. However, would you mind to do one more case fore them?

威因，我知道你心底不太能认同大顺军，可是你愿意看在我的面子上，再替他们办件事吗？

youdao

Some of the original stone markers can still seen at the prize-winning winery Quinta Nova da Nossa Senhora do Carmo, one of dozens of local quintas (estates) where you can dine or stay in charming and authentic surroundings.

BBC: The changing landscape of the Douro River Valley