各种初一数学计算题...

计算

1、5ab³×(-4分之3a³b²)×(-3分之2ab^4c)³

=[5*(-3/4)*(-2/3)³]*[ab³*a³b²*(ab^4c)³]

=[5*(-3/4)*(-8/27)]*[ab³*a³b²*a³b^12c³]

=10/9*a^7b^17c³

2、x(x-1)(x+3)-x²(x+1)+3x-1

=x(x²+2x-3)-x³-x²+3x-1

=x³+2x²-3x-x³-x²+3x-1

=x²-1

分解因式

3、-16m²-48m^4+24m^6

=8m²(3m^4-6m²-2)

4、25x²-16y²

=(5x)²-(4y)²

=(5x-4y)(5x+4y)

5、ab²-4ab+4a

=a(b²-4b+4)

=a(b-2)²

6、a³+a²-a-1

=a²(a+1)-(a+1)

=(a+1)(a²-1)

=(a+1)(a+1)(a-1)

=(a+1)²(a-1)