8ab-{4a-3[6ab+5(ab+a-b)-7a]-2}这道题怎么做
问题描述：
8ab-{4a-3[6ab+5(ab+a-b)-7a]-2}这道题怎么做
答
8ab-{4a-3[6ab+5(ab+a-b)-7a]-2}
=8ab-[4a-3(6ab+5ab+5-5b-7a)-2]
=8ab-[4a-3(11ab-7a-5b+5)-2]
=8ab-(4a-33ab+21a+15b-15-2)
=8ab-(25a-33ab+15b-17)
=8ab-25a+33ab-15b+17
=41ab-25a-15b+17
答
从里往外算：=8ab-{4a-3[6ab+5ab+5a-5b-7a]-2}
=8ab-{4a-18ab-15ab-15a+15b+21a-2}
=8ab-4a+18ab+15ab+15a-15b-21a+2
=41ab-10a-15b+2
也不说给点悬赏!汗