-3(2a-ab²)+4(a+ab²-5);

问题描述:

-3(2a-ab²)+4(a+ab²-5);
1/2x-2(x-y²)-(3/2x+y²)

-3(2a-ab²)+4(a+ab²-5);
=7ab²-2a-20
1/2x-2(x-y²)-(3/2x+y²)
=-3x+y²