Due to the bad weather, cotton yield poer mu is very low this year.

由于天气不好，今年棉花的亩产量很低。

And each began cohabitating with humans at different times in our evolutionary history. For example, " Mus musculus domesticus."

在我们进化史的不同时期，每种老鼠都开始类共存的生活。比如, “家鼠。”

" mu" " k" times " Fn" and the " mu" " k"

" mu" " k" 乘以 " Fn" 并且 " mu" " k" 将 0.

And then the last term is minus mu times minus mu, which is plus mu squared.

后最后一项减 mu 乘以减 mu，即加 mu 的平方。

We learned the population mean was that mu letter.

我们解到口那个 mu 字母。

The force of friction is always mu K FN.

摩擦力始终为 mu K FN。

One mu equals roughly 0.067 hectares.

一亩约等于 0. 067 公顷。

" Mus musculus domesticus" .It began raiding human pantries around 12,000 years ago.

“Mus musculus domesticus”。大约在 12,000 年前，它开始袭击类的储藏室。

" Now me mus tuddy my lessin, " went on the funny little thing.

“现在我必须好好学习， ” 那个有趣的小东西继续说道。

So pi mu is what we're working on.

所以π我们正在研究的东西。

So minus mu K so the force of friction--- I'll just put force of friction.

所以减去 mu K 所以摩擦力 --- 我只输入摩擦力。

And actually, we could have just left the mu squared there.

实际上，我们本可以将 mu 平方留在那里。

So this is the Greek letter mu, and we put this k here for kinetic, or we can kind of say moving friction.

k表示" 动" (kinetic)该系数等于摩擦力的大小。

Times mu squared times the sum from i equals 1 to n.

乘以 mu 的平方乘以 i 等于 1 到 n 的总和。

And let's see, minus 2 times mu-- sorry, that mu doesn't look good.

让我们看看，减去 2 乘以 mu-- 抱歉，mu 看起来不太好。

So the mu squared term just gets factorized out.

所以 mu 平方的项刚好被分解。

I'm interested in understanding this as a function of mu.

我有兴趣将其理解为 mu 的函数。

Similarly, the expected value for  our sum of size 3 is 3 times mu and so on and so forth.

同样，大小 3 的总和的预期为 mu 的 3 倍，依此类推。

I've got a mu squared term in here, and I've got two things that go in there.

我这里有一个 mu 平方项，我有两样东西。

Fx bar given mu and sigma squared.

Fx bar 给定 mu 和 sigma 平方。