y OK, so let's say that we have a function of two variables, x and y.
假设有一个函数含有2个变量x和。
So, we said when we have a function of two variables, we have the gradient vector.
我们说，当一个二元函数存在时，就有梯度向量。
we've seen is how to actually view a function of two variables in terms of its graph and its contour plot.
我们学过怎样认识二元函数,从它的图像和等高线的角度来看。
I should say that is for a function of two variables to try to decide whether a given critical point is a minimum, a maximum or a saddle point.
但这种办法并不普遍，只能用于二元函数，来判断是极小值点、极大值点还是鞍点。
This example returns the length of the third side of a right triangle by applying the SQUARE function to two variables and then calculating the square root of their sum.
此示例通过对两个变量应用SQUARE函数然后计算其和的平方根，返回直角三角形第三边的长度。
Chapter two briefly introduces the origin and function of market subdivision as well as the variables in market subdivision.
第二章简要介绍了市场细分的产生、作用以及市场细分变量要素。
By using the limits of functions and the exchange limit theorem, we considered the relationship between the double limit of function with two variables and its repeated limits.
应用函数列的极限与函数的极限交换次序定理，研究了二元函数的二重极限与它的两个累次极限的关系定理，研究了二元函数的两个二阶混合偏导数可交换次序定理。
After summing up, summarizing, find some laws: Choosing proper route to confirm the function limit of two variables' doesn't exist.
经过归纳，总结，找到一些规律：即选择适当路径以确定二元函数极限不存在。
After summing up, summarizing, find some laws: Choosing proper route to confirm the function limit of two variables' doesn't exist.
经过归纳，总结，找到一些规律：即选择适当路径以确定二元函数极限不存在。
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