quartic equation

高評価: 146件

再生: 10,463回

公開日: 2019年6月09日

(manuscript)
1) Hello everyone. Today, I 'm going to talk in English.
2) In fact, this is the fourth time to make English video.
3) I don't speak English in everyday life, and I am not good at English.
4) So, before taking this video, I made a manuscript by Google translation.
5) To be honest,There is a manuscript here and I 'm speaking from it.
6) Now, let's get started. we want to solve this quartic equation.
7) Let's make it as easy as possible.
8) Pay attention to the fact that the numbers in all parentheses are increasing by three.
9) So Let's expand in this order,
10) The point is that the coefficient of x in each parenthesis are equal.
11) Then think of x square + 11x as one block and expand like this.
12) Surprisingly, the constant term becomes 19 square, thus we can factorize this.
13) Well, I set the numbers to be able to calculate like this.
14) After that, the inside of the parenthesis becomes zero, so we can use the quadratic formula to get the anwer.
15) In this problem, we were able to calculate by paying attention to the regular increase in the parentheses.
16) that's all for today. Please point out something unusual in English expression.