3(x-1)³y-(1-x)³z,其中x=1/2,y=1/5,z=-6/5先化简,再求值._数学解答

3(x-1)³y-(1-x)³z,其中x=1/2,y=1/5,z=-6/5先化简,再求值.

人气：118 ℃　时间：2020-07-04 20:18:24

解答

3(x-1)³y-(1-x)³z
=3(x-1)³y+(x-1)³z
=(x-1)³(3y+z)
=(1/2-1)³(3×1/5-6/5)
=-1/8×(-3/5)
=3/40