3a²-9aba四次方-1x²-y²-2y-1x²-3x+4

3a²-9aba四次方-1x²-y²-2y-1x²-3x+4
3a²-9ab
a四次方-1
x²-y²-2y-1
x²-3x+4

3a²-9aba四次方-1x²-y²-2y-1x²-3x+4
3a²-9ab
=3a(a-3b)
a四次方-1
=(a²+1)(a²-1)
=(a²+1)(a+1)(a-1)
x²-y²-2y-1
=x²-(y²+2y+1)
=x²-(y+1)²
=(x+y+1)(x-y-1)
x²-3x+4
无法分解

解
3a²-9ab
=3a(a-3b)
a^4-1
=(a²-1)(a²+1)
=(a-1)(a+1)(a²+1)
x²-y²-2y-1
=x²-(y²+2y+1)
=x²-(y+1)²
=(x-y-1)(x+y+1)
x²-3x+4
=(x-4)(x+1)