计算这几题 也就是去括号和化简.
来源:学生作业帮 编辑:神马作文网作业帮 分类:数学作业 时间:2024/11/12 06:15:19
计算这几题 也就是去括号和化简.
(1)4a^3b-3a^2b^2
(2)x²y-xy²
(3)a^2-4a
(4)-a^3+2a^2-3a+15
(5)-ab(a+1)
(6)8m²-8m-2
(7)-3a²+34a-13
(8)5x^2-9/2x-3
再问: 能写上过程吗? 去括号和化简的过程
再答: (1)(4a^3b-10b^3)+(-3a^2b^2+10b^3) =4a^3b-10b^3-3a^2b^2+10b^3 =4a^3b-3a^2b^2 (2)(4x^2y-5xy^2)-(3x^2y-4xy^2) =4x²y-5xy²-3x²y+4xy² =x²y-xy² (3)5a^2-[a^2+(5a^2-2a)-2(a^2-3a)] =5a^2-[a^2+5a^2-2a-2a^2+6a] =5a^2-[4a^2+4a] =a^2-4a (4)15+3(1-a)-(1-a-a^2)+(1-a+a^2-a^3) =15+3-3a-1+a+a^2+1-a+a^2-a^3 =-a^3+2a^2-3a+15 (5)4a^2b-3ab+(-5a^2b+2ab) =-a^2b-ab =-ab(a+1) (6)6m²-4m-3+2m²-4m+1 =8m²-8m-2 (7)(5a²+2a-1)-4(3-8a+2a²) =5a²+2a-1-12+32a-8a² =-3a²+34a-13 (8)3x^2-[5x-(1/2x-3)-2x^2] =3x^2-5x+(1/2x-3)+2x^2 =5x^2-5x+1/2x-3 =5x^2-9/2x-3
(2)x²y-xy²
(3)a^2-4a
(4)-a^3+2a^2-3a+15
(5)-ab(a+1)
(6)8m²-8m-2
(7)-3a²+34a-13
(8)5x^2-9/2x-3
再问: 能写上过程吗? 去括号和化简的过程
再答: (1)(4a^3b-10b^3)+(-3a^2b^2+10b^3) =4a^3b-10b^3-3a^2b^2+10b^3 =4a^3b-3a^2b^2 (2)(4x^2y-5xy^2)-(3x^2y-4xy^2) =4x²y-5xy²-3x²y+4xy² =x²y-xy² (3)5a^2-[a^2+(5a^2-2a)-2(a^2-3a)] =5a^2-[a^2+5a^2-2a-2a^2+6a] =5a^2-[4a^2+4a] =a^2-4a (4)15+3(1-a)-(1-a-a^2)+(1-a+a^2-a^3) =15+3-3a-1+a+a^2+1-a+a^2-a^3 =-a^3+2a^2-3a+15 (5)4a^2b-3ab+(-5a^2b+2ab) =-a^2b-ab =-ab(a+1) (6)6m²-4m-3+2m²-4m+1 =8m²-8m-2 (7)(5a²+2a-1)-4(3-8a+2a²) =5a²+2a-1-12+32a-8a² =-3a²+34a-13 (8)3x^2-[5x-(1/2x-3)-2x^2] =3x^2-5x+(1/2x-3)+2x^2 =5x^2-5x+1/2x-3 =5x^2-9/2x-3