证明a^n-b^n=(a-b)(a^n-1 + a^n-2 b +.+a b^n-2 + b^n-1)a^n-b^n=(a-b)(a^n-1 + a^n-2 b +.+a b^n-2 + b^n-1)证明
来源:学生作业帮助网 编辑:作业帮 时间:2024/11/05 20:26:44
证明a^n-b^n=(a-b)(a^n-1 + a^n-2 b +.+a b^n-2 + b^n-1)a^n-b^n=(a-b)(a^n-1 + a^n-2 b +.+a b^n-2 + b^n-1)证明
证明a^n-b^n=(a-b)(a^n-1 + a^n-2 b +.+a b^n-2 + b^n-1)
a^n-b^n=(a-b)(a^n-1 + a^n-2 b +.+a b^n-2 + b^n-1)
证明
证明a^n-b^n=(a-b)(a^n-1 + a^n-2 b +.+a b^n-2 + b^n-1)a^n-b^n=(a-b)(a^n-1 + a^n-2 b +.+a b^n-2 + b^n-1)证明
不太好说明.
学过多项式除法的话可以直接求出(a^n-b^n)/(a-b)=a^(n-1)+ a^(n-2)*b +.+a*b^(n-2) + b^(n-1).
也可以直接拆开右边.有
右边= a*[a^(n-1)+ a^(n-2)*b +.+a*b^(n-2) + b^(n-1)]
- b*[a^(n-1)+ a^(n-2)*b +.+a*b^(n-2) + b^(n-1)]
= a^n + a^(n-1)*b + a^(n-2)*b^2 +.+ a^2*b^(n-2) + a*b^(n-1)
-[b^n + b^(n-1)*a + b^(n-2)*a^2 +.+ b^2*b^(a-2) + b*a^(n-1)]
= a^n + a^(n-1)*b + a^(n-2)*b^2 +.+ a^2*b^(n-2) + a*b^(n-1)
-[b^n + b*a^(n-1) + b^2*b^(a-2) +.+ b^(n-2)*a^2 + b^(n-1)*a] (颠倒第二行的顺序,发现可以上下对应消去)
= a^n - b^n=左边.证毕.
=a^n+a^n-1b+.....ab^n-1-(a^n-1b+a^n-2b+....b^n)
=a^n-b^n
Even if only sad memories
even if only for my painful memories
or
I want to forget the memory of
If I could bravely bear
not escape to push hard, then One day I will be ...
全部展开
Even if only sad memories
even if only for my painful memories
or
I want to forget the memory of
If I could bravely bear
not escape to push hard, then One day I will be able to get
strong and no longer afraid of these memories
I believed this because I want to believe
because I want to have no memories of his thought is
... ...
forgetting stuff, even if
because I believe that one day all
to move beyond that to treasure memories to remain forever hidden heart
相关的主题文章:
Wan Chuk Yuen Travels
Sportsman develop Cheats
Never toothache Qi Fang
收起