Do you mean how do I know that it is perpendicular to a level curve?

你想问的是，我如何知道它是和等高线垂直的吗？

youdao

So, the level curve corresponding to zero is actually two diagonal lines.

0的等高线实际上是两条对角线。

youdao

So, well, maybe we want to understand first what happens if we move inside the level curve, OK?

我们首先要理解,移动到等值曲线的内部会发生什么？

youdao

The BlackBerry maker continues to grow in Latin America, for example, due to the success of the Curve 8520 entry-level model, which has helped drive growth in most emerging markets.

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There is an optimal tax level to maximise tax income, the same type of curve applies to government and economic strength.

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"Even though his learning curve had to be very quick given his experience level coming into this he did an amazing job, " Mozeliak said.

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