先化简再求值a^3(-b^3)+(-1/2ab^2)^3,其中a=1/4,b=4

先化简再求值a^3(-b^3)+(-1/2ab^2)^3,其中a=1/4,b=4
先化简再求值a^3(-b^3)+(-1/2ab^2)^3,其中a=1/4,b=4

先化简再求值a^3(-b^3)+(-1/2ab^2)^3,其中a=1/4,b=4
a^3(-b^3)^2+(-1/2ab^2)^3,其中a=1/4,b=4
=a^3b^6-1/8a^3b^6
=7/8a^3b^3*b^3
=7/8(ab)^3*b^3
=7/8*1*64
=56

a^3(-b^3)^2+(-1/2ab^2)^3=7/8a^3b^6
值为7/8*4^3=56

a^3(-b^3)+(-1/2ab^2)^3=-a^3b^3-1/8a^3b^6=a^3b^3(-1-1/8b^2)带入数据得(1/4)^3*4^3[-1-1/8*(4)^2]=-3