tangent line

基本解释

So, if I draw the tangent line to this slice, x then the slope will be partial f of partial x.
如果画出这个切片的切线，那么斜率就是∂f/∂
And visually what we're accomplishing is somehow to take the hyperbola, and take a point on the hyperbola, and figure out some tangent line.
从视觉上看，我们要做的是，想办法，在这个反函数，在反函数上取一个点，设法找出切线。
If the two level curves are tangent to each other that means they have the same tangent line. That means that the normal vectors should be parallel. Let me maybe draw a picture here.
如果两个等高线相切，说明它们的切线相同,也就是说他们的法向量应该平行,我再在这里画个图。

Show me a place where that's not true where the tangent line will be really bad.
请给我个这个原则不对的例子,也就是说切线没起到相应作用的例子。
麻省理工公开课 - 计算机科学及编程导论课程节选
That means that you want to pick, ultimately, a point on this-- this line is tangent to the efficient portfolio frontier with all the other assets in it.
那意味着你会最终会在这上面选一个点-,这条直线是与有效边界相切的,后者包含了所有的资产组合。
耶鲁公开课 - 金融市场课程节选
I don't know how well you can see it in this figure here, is the slope of a straight line connecting these two points, and as the points come closer and closer, the straight line would become tangent to the curve.
我不清楚你们对于这个图像的理解,这条连接两点的斜线,随着两点距离逐渐缩小,两点连线会变成曲线的切线
耶鲁公开课 - 基础物理课程节选