(2x - 7)3 = 125
(2x - 7)3 = 53
cùng bỏ đi mũ 3
2x - 7 = 5
2x = 5 + 7
2x = 12
x = 12 : 2
x = 6
Bằng 6 nha
(2x - 7)3 = 125
\(\Rightarrow\)(2x - 7)3 = 53
\(\Rightarrow\)2x - 7 = 5
\(\Rightarrow\)2x = 12
\(\Rightarrow\)x = 6
\(\left(2x-7\right)^3=125\)
\(\left(2x-7\right)^3=5^3\)
\(\Rightarrow2x-7=5\)
\(\Rightarrow2x=12\)
\(\Rightarrow x=6\)
vay \(x=6\)
Ta có:
\(\left(2x-7\right)^3=125\)
\(\Leftrightarrow\left(2x-7\right)^3=5^3\)
\(\Rightarrow2x-7=5\)
\(\Leftrightarrow2x=12\)
\(\Rightarrow x=6\)
P/s : Chúng ta nên đặt dấu \("\Leftrightarrow"\)và\("\Rightarrow"\)cho đúng vị trí
(2x-7)3=125
(2x-7)3=53
2x-7=5
2x=5+7
2x=12
X=12:2
X=6
