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。

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One of the most famous works of art in the world is Leonardo da Vinci's Mona Lisa.

世界上最著名的艺术作品之一是列奥纳多·达·芬奇的《蒙娜丽莎》。

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None of the objects yet discovered by NASA's Near earth objects program have a high probability of hitting the earth — though one known as 1950 DA will come extremely close in 2880.

有一些还未被美国宇航局近地天体计划发现的小行星，很有可能会撞击我们的地球，一个被称为1950 DA的现象很有可能在2880年出现。

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He showed a picture of Leonardo da Vinci's famous "Mona Lisa" painting to one hundred school children from poor city neighborhoods.

VOA: special.2010.07.09

The " Salvator Mundi" was, for years, thought to be a painting by one of da Vinci's pupils or associates.

CNN: Are there more lost Leonardo paintings out there?

What a gift it is to have one of Leonardo da Vinci's notebooks, small enough to have sat in his palm, on permanent view for the first time.

ECONOMIST: The new Medieval and Renaissance galleries are a treat

One of the most challenging trajectories, officials said, is the one to Sao Gabriel da Cachoeira, a densly-forested area in the Amazon.

CNN: STORY HIGHLIGHTS