ez :))
\(\left(2x++1\right)^3=5^3\)
\(\Rightarrow2x+1=5\)
\(\Rightarrow x=2\)
Xong nhé
(2x+1)3 =125
(2x+1)3 =53
=> 2x+1=5
=> 2x=4
=> x=2
\(\left(2x+1\right)^3=125\)
\(^{\Leftrightarrow\orbr{\begin{cases}\left(2x+1\right)^3=5^3\\\left(2x+1\right)^3=\left(-5^3\right)\end{cases}\Leftrightarrow}\orbr{\begin{cases}2x+1=5\\2x+1=-5\end{cases}\Leftrightarrow}\orbr{\begin{cases}2x=4\\2x=-6\end{cases}\Leftrightarrow}\orbr{\begin{cases}x=2\\x=-3\end{cases}}}\)
Vậy x=2; x=-3
(2x + 1 ) ^3 = 125
( 2x + 1 ) ^ 3 = 5^3
=> 2x + 1 = 5
2x = 5 - 1
2x = 4
=> x = 4 : 2
x = 2
\(\left(2x+1\right)^3=125\)
\(\Leftrightarrow\left(2x+1\right)^3=5^3\)
\(\Leftrightarrow2x+1=5\)
\(\Leftrightarrow2x=5-1\)
\(\Leftrightarrow2x=4\)
\(\Leftrightarrow x=4\div2\)
\(\Leftrightarrow x=2\)
Vậy ............
