Question

先化简再求值

a的立方乘(-b³)²+(-½ab²),其中a=¼,b=4

急急急急急急急
哦抱歉题目是a的立方乘(-b³)²+(-½ab²)³,其中a=¼,b=4
咱效率点儿好不
之后再给＋5分行不行
就给个答案不写过程也行

Answer 1

解a的立方乘(-b³)²+(-½ab²)
=a³b^6-1/2ab
=(1/4)³*4^6-1/2*1/4*4
=(1/4)³*4^3*4^3-1/2*1/4*4
=(1/4*4)³*4^3-1/2*1/4*4
=4^3-1/2
=64-1/2
=127/2

追问

抱歉我题目打错了，拜托再看下呗
拜托啊

追答

解a的立方乘(-b³)²+(-½ab²)³
=a³b^6-1/8a³b^6
=7/8a³b^6
=7/8(1/4)³4^6
=7/8(1/4)³4^3*4^3
=7/8(1/4*4)³*4^3
=7/8*4^3
=7/8*64
=56