计算①2(x+1)(x-1)-x(2x+1)②2x7y3÷x3y+(3x2y)2-(x2)2•(-2y)2.
题型:解答题难度:一般来源:不详
计算 ①2(x+1)(x-1)-x(2x+1) ②2x7y3÷x3y+(3x2y)2-(x2)2•(-2y)2. |
答案
①原式=2x2-2-2x2-x=-2-x; ②原式=2x4y2+9x4y2-4x4y2=7x4y2. |
举一反三
先化简,再求值(3x-y)2-2(3x-y)(3x+y)+(3x+y)2,其中x=4,y=-. |
计算: (1)2a•a3+3a7÷a3 (2)(x+4)(2x-1)+(x+2)(x-2) |
计算: (1)=______; (2)=______; (3)=______; (4)(2b)3=______; (5)4y•(-2xy2)=______; (6)28x4y2÷7x3y=______; (7)(a+b)(a-b)=______. |
(1)-+|1-| (2)(-2a2b)2•(6ab)÷(-3b2) (3)(2x-1)(3x+2)-6x(x-2) (4)(3x-y)2-(3x+2y)(3x-2y) |
先化简,再求值:[(x+y)(x-y)-(x-y)2+2y(x-y)]÷4y,其中x=-2-,y=2-. |
最新试题
热门考点