首页 > 数学 > 题目详情
计算:(a+2)(a-2)-(2a-1)²+(a+1)²;(x-6)(x²+x+1)-x(2x+1)(3x-1).
题目内容:
计算:(a+2)(a-2)-(2a-1)²+(a+1)²;(x-6)(x²+x+1)-x(2x+1)(3x-1).优质解答
(a+2)(a-2)-(2a-1)²+(a+1)²
=a²-4-(4a²-4a+1)+(a²+2a+1)
=a²-4-4a²+4a-1+a²+2a+1
=-2a²+6a-4
(x-6)(x²+x+1)-x(2x+1)(3x-1)
=x³+x²+x-6x²-6x-6-x(6x²+x-1)
=x³-5x²-5x-6-6x³-x²+x
=-5x³-6x²-4x-6
优质解答
=a²-4-(4a²-4a+1)+(a²+2a+1)
=a²-4-4a²+4a-1+a²+2a+1
=-2a²+6a-4
(x-6)(x²+x+1)-x(2x+1)(3x-1)
=x³+x²+x-6x²-6x-6-x(6x²+x-1)
=x³-5x²-5x-6-6x³-x²+x
=-5x³-6x²-4x-6
本题链接: