Question

计算：3(a2b-ab2)+[

3

2

a2b-

1

3

(a2b-ab2)]-[

1

2

ab2+

8

3

(a2b-ab2)]．

Answer 1

原式=3a²b-3ab²+[

3

2

a²b-

1

3

a²b+

1

3

ab²]-[

1

2

ab²+

8

3

a²b-

8

3

ab²]
=3a²b-3ab²+

3

2

a²b-

1

3

a²b+

1

3

ab²-

1

2

ab²-

8

3

a²b+

8

3

ab²
=（3+

3

2

-

1

3

-

8

3

）a²b-（3-

1

3

+

1

2

-

8

3

）ab²
=

3

2

a²b-

1

2

ab²．