人教版初中七上数学书75页的4到5题的答案

如题所述

第1个回答  2014-01-31
(1)=4a³b-10b³-3a²b²+10b³
=4a³b-3a²b²
(2)
(3)=5a²-a²-(5a²-2a)+2(a²-3a)
=4a²-5a²+2a+2a²-6a
=a²-4a
(4)

(5)=-a²b-ab
=-ab(a+1)

(6)=6m²-4m-3+2m²-4m+1
=8m2-8m-2
=2(4m2-4m-1)

(7)=5a²+2a-1-12+32a-8a²
=-3a²(8)=3 x²-5x+(1/2x-3)-2x²
=3 x²-5x+1/2x-3-2x²
= x²-9/2x-3追问

谢谢,第五题有答案吗

追答

2. (4x²y-5xy²)-(3x²y-4xy²)
=4x²y-5xy²-3x²y+4xy²
= x²y- xy²
=xy(x-y)

4. 15+3(1-a)-(1-a-a²)+(1-a+a²-a³)
=15+3-3a-1+a+a2+1-a+a2-a3
=18-3a+2a2-a3

5,先化简,再求值
5x²+4-3x²-5X-2x²-5+6X
=5x²-3x²-2x²+6X-5X+4-5
=X-1
=-3-1
=-4

8.8. 3x²-(5x-(1/2x-3)+2x²)
=3 x²-5x+(1/2x-3)-2x²
=3 x²-5x+1/2x-3-2x²
= x²-9/2x-3

第2个回答  2014-01-31
能把题目发过来吗追问

那好麻烦的