19/25*76(3/7-1/34)*7-27/34能簡便的要簡算,謝

19/25*76(3/7-1/34)*7-27/34能簡便的要簡算,謝


1.
76=4*19
19/25*76=19/19/(4*25)=1/100
2.
(3/7-1/34)*7-27/34 =3/7*7-7/34-27/34
=3-(7/34+27/34)=3-1=2



-27(x-1)³;=-1000的x的值


(x-1)³;=-1000/-27=1000/27=(10/3)³;
x-1=10/3
x=13/3



算一下這個題,1/1000(0.1x+10)³;=-27


1/1000*(0.1x+10)^3=-27
[(1/10)*(0.1x+10)]^3=(-3)^3
(1/10)*(0.1x+10)=-3
0.1x+10=-30
0.1x=-40
x=-400