x²-3xy+2y²+x-2因式分解

x²-3xy+2y²+x-2因式分解
x²-3xy+2y²+x-2因式分解

x²-3xy+2y²+x-2因式分解
(x-2y+2)(x-y-1)

x²-3xy+2y²+x-2
=（x²-3xy+2y²)+(x-2)
=(x-y)(x-2y)+(x-2)

f(x,y)=x²-3xy+2y²+x-2
f(y+1,y) =0
(x-(y+1)) is a factor
f(x,y ) = (x-(y+1))(x + ay+b)
f(0,0) = -2 = -b
b = 2
f(0,1) = 0 = -2(a+2)
a=-2
f(x,y) = (x-y-1)(x - 2y+2)