(1/2a^3-3/4a+5/6)-4(-1/8a^3+1/16a-7/24)

问题描述:

(1/2a^3-3/4a+5/6)-4(-1/8a^3+1/16a-7/24)

(1/2a^3-3/4a+5/6)-4(-1/8a^3+1/16a-7/24)
=1/2a^3-3/4a+5/6+1/2a^3-1/4a+7/6
=a^3-a+2