分解因式 x²-6xy+5y²; m²-5m-6; m²-m-6; 3x²+13x-10; 6m²+m-12.x²-2xy+y²-5x+5y-6;x³-x²-x+1;1-x²+4xy-4y²;a²-b²-c²+2bc;计算(a-b)²+2(a-b)(b-c)+(c-b)²的值,其中a-c=—1.4.
问题描述:
分解因式 x²-6xy+5y²; m²-5m-6; m²-m-6; 3x²+13x-10; 6m²+m-12.
x²-2xy+y²-5x+5y-6;
x³-x²-x+1;
1-x²+4xy-4y²;
a²-b²-c²+2bc;
计算(a-b)²+2(a-b)(b-c)+(c-b)²的值,其中a-c=—1.4.
答
x²-6xy+5y²
=(x-5y)(x-y)
m²-5m-6
=(m-6)(m+1)
m²-m-6
=(m-3)(m+2)
3x²+13x-10
=(3x-2)(x+5)
6m²+m-12
=(2m+3)(3m-4)
x²-2xy+y²-5x+5y-6;
=(x-y)²-5(x-y)-6
=(x-y-6)(x-y+1)
x³-x²-x+1
=x²(x-1)-(x-1)
=(x-1)(x²-1)
=(x-1)²(x+1)
1-x²+4xy-4y²
=1-(x-2y)²
=(1+x-2y)(1-x+2y)
a²-b²-c²+2bc
=a²-(b-c)²
=(a+b-c)(a-b+c)
计算(a-b)²+2(a-b)(b-c)+(c-b)²的值,其中a-c=—1.4。
(a-b)²+2(a-b)(b-c)+(c-b)²
=(a-b+b-c)²
=(a-c)²
=1.4²
=1.96
答
x²-2xy+y²-5x+5y-6;=(x-y)²-5(x-y)+6=(x-y-2)(x-y-3)x³-x²-x+1;=x²(x-1)-(x-1)=(x-1)(x²-1)=(x-1)²(x+1)1-x²+4xy-4y²;=1-(x-2y)²=(1+x-2y)(1-x+2y)a...