1:已知m=x-y,n=xy,试用m,n表示(x³+y³﹚²,2:当x=-1时,x³+2x²﹣5x-6=0,请根据这一事实,将x³+2x²-5x+6分解因式.没分了,不好意思,
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![1:已知m=x-y,n=xy,试用m,n表示(x³+y³﹚²,2:当x=-1时,x³+2x²﹣5x-6=0,请根据这一事实,将x³+2x²-5x+6分解因式.没分了,不好意思,](/uploads/image/z/754021-37-1.jpg?t=1%EF%BC%9A%E5%B7%B2%E7%9F%A5m%3Dx-y%2Cn%3Dxy%2C%E8%AF%95%E7%94%A8m%2Cn%E8%A1%A8%E7%A4%BA%EF%BC%88x%26%23179%3B%2By%26%23179%3B%EF%B9%9A%26%23178%3B%2C2%EF%BC%9A%E5%BD%93x%3D-1%E6%97%B6%2Cx%26%23179%3B%EF%BC%8B2x%26%23178%3B%EF%B9%A35x-6%3D0%2C%E8%AF%B7%E6%A0%B9%E6%8D%AE%E8%BF%99%E4%B8%80%E4%BA%8B%E5%AE%9E%2C%E5%B0%86x%26%23179%3B%EF%BC%8B2x%26%23178%3B-5x%2B6%E5%88%86%E8%A7%A3%E5%9B%A0%E5%BC%8F.%E6%B2%A1%E5%88%86%E4%BA%86%2C%E4%B8%8D%E5%A5%BD%E6%84%8F%E6%80%9D%2C)
1:已知m=x-y,n=xy,试用m,n表示(x³+y³﹚²,2:当x=-1时,x³+2x²﹣5x-6=0,请根据这一事实,将x³+2x²-5x+6分解因式.没分了,不好意思,
1:已知m=x-y,n=xy,试用m,n表示(x³+y³﹚²,
2:当x=-1时,x³+2x²﹣5x-6=0,请根据这一事实,将x³+2x²-5x+6分解因式.没分了,不好意思,
1:已知m=x-y,n=xy,试用m,n表示(x³+y³﹚²,2:当x=-1时,x³+2x²﹣5x-6=0,请根据这一事实,将x³+2x²-5x+6分解因式.没分了,不好意思,
1. (x³+y³﹚² = (x+y)²(x²-xy+y²)²
(x+y)² =x²+2xy+y² =( x-y)² +4xy = m² + 4n
x²-xy+y² =( x-y)² +xy = m² + n
(x³+y³﹚² = ( m²+4n)(m²+n)²
2. 当x=-1时,x³+2x²﹣5x-6=0 ,也就是说x+1是x³+2x²﹣5x-6得分解因式
用x³+2x²﹣5x-6 除以x+1得 x²+x-6
x²+x-6 = (x-2)(x+3)
故x³+2x²﹣5x-6=(x+1) (x-2)(x+3)
(x³+y³﹚²
=(x+y)²(x²-xy+y²)²
=[(x-y)²+4xy][(x-y)²+xy]²
=(m²+4n)(m²+n)²
=……
x³+2x²-5x-6
=x³+1+2x²-5x-7
=(x+1)(x²-x+1)+(2x-7)(x+1)
=(x+1)(x²+x-6)
=(x+1)(x+3)(x-2)
前面的答案差不多了啦。。。