我们首先介绍了高阶等差数列前 n 项和的求解方法。

We first introduce methods of finding the sum of the first n terms for an arithmetic sequence of higher order.

youdao

目前，美国对华贸易逆差数额庞大。

The United States is currently running a large bilateral trade deficit with China.

youdao

与美国经济之间的增长差数已收窄，预计今年还会进一步缩减。

The growth differential with America's economy has narrowed and is expected to contract further this year.

youdao