YLL討論網

Raceleader · 由 **Raceleader** 於星期二四月 01, 2003 10:31 am

n是非負整數，n≧0：
我們有a₀ = a₁ = a₂ = 1
而且a_n+3 = a_n+2 + a_n+1 + a_n
求a_n的一般式

---- · 由 **----** 於星期二四月 01, 2003 3:38 pm

I dare not use cubic formula to find the roots of x^3-x^2-x-1=0~~~

Raceleader · 由 **Raceleader** 於星期二四月 01, 2003 3:47 pm

I have used Mathematica to check, the result is very ugly.

---- · 由 **----** 於星期二四月 01, 2003 3:52 pm

of coz, becoz the roots of x^3-x^2-x-1=0 are so...
If you change the question a bit, it will be much much easier.

E.T · 由 **E.T** 於星期二四月 01, 2003 3:56 pm

What is 'cubic formula' ?

Raceleader · 由 **Raceleader** 於星期二四月 01, 2003 4:03 pm

三次方程式
e.g. x³-2x²+3x-4=0

E.T · 由 **E.T** 於星期二四月 01, 2003 4:29 pm

How to find 三次方程式 answer ? Have some method to solve this ?
I have not study this , because my teacher teach very slow

---- · 由 **----** 於星期二四月 01, 2003 4:52 pm

This is not taught in school, if you like, you may go to my site as reference.
http://hk.geocities.com/mathsworld2001/themes/020110.htm

[數學]求a(n)的一般式，2000