a) (x-1)3 = 125
(x-1)3 = 53
=> x-1 = 5
x = 5+1
x = 6
Vậy x = 6.
b) (2x+1)3 = 343
(2x+1)3 = 73
=> 2x + 1 = 7
2x = 7+1
2x = 8
x = 8 : 2
x = 4
Vậy x = 4
a)(x-1)^3=125
(x-1)^3=5^3
x-1=5
x=5+1
x=6
vậy x=6
b)(2x+1)^3=343
(2x-1)^3=7^3
2x-1=7
2x=7+1
2x=8
x=8:2
x=4
vậy x=4