(xy+1)(x+1)(y+1)+xy=0國中 回應 piggy Re: 因式分解 2009-01-11 22:02 (xy+1)(x+1)(y+1)+xy =(xy+1)(xy+x+y+1)+xy =(xy+1)(xy+1+x+y)+xy =(xy+1)^2+(xy+1)(x+y)+xy (用十字交乘法) =(xy+1+x)(xy+1+y)
piggy Re: 因式分解 2009-01-11 22:02 (xy+1)(x+1)(y+1)+xy =(xy+1)(xy+x+y+1)+xy =(xy+1)(xy+1+x+y)+xy =(xy+1)^2+(xy+1)(x+y)+xy (用十字交乘法) =(xy+1+x)(xy+1+y)
回應
piggy
Re: 因式分解
2009-01-11 22:02=(xy+1)(xy+x+y+1)+xy
=(xy+1)(xy+1+x+y)+xy
=(xy+1)^2+(xy+1)(x+y)+xy (用十字交乘法)
=(xy+1+x)(xy+1+y)