因式分解高手！

f(x)=x^2-5x-6
You can substitute some values of x
for example x=-1
f(-1)=1+5-6=0
So, x+1 is a factor of x^2-5x-6
Then by long division,
f(x)=(x+1)(x-6)
It is true for x^n where n is a natural number and it contains linear factors

2007-08-08 23:07:42 補充：
This is factor theorem. Search!!!

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