a)\(\left(2x+1\right)^3=5^3\)
\(\Rightarrow2x+1=5\)
\(2x=5-1\)
\(2x=4\)
\(x=4:2\)
\(x=2\)
\(b,\left(2x-1\right)^3=125\)
\(\Rightarrow2x-1=5\)
\(2x=5+1\)
\(2x=6\)
\(x=6:2=3\)
b) \(\left(2x-1\right)^3=125\)
\(\left(2x-1\right)^3=5^3\)
\(2x-1=5\)
\(2x=5+1\)
\(2x=6\)
\(x=6:2\)
\(x=3\)
c) \(4x^3+15=19\)
\(4x^3=19+15\)
\(4x^3=34\)
\(x^3=\frac{34}{4}=\frac{17}{2}\)
Chỗ này có vẻ hơi sai sai ạ :33
d) \(\left(x+1\right)^2=4\)
\(\Rightarrow\orbr{\begin{cases}x+1=2\\x+1=-2\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x=1\\x=-3\end{cases}}\)
e) \(\left(x-1\right)^3=64\)
\(\left(x-1\right)^3=4^3\)
\(x-1=4\)
\(x=4+1\)
\(x=5\)
f) \(\left(x-1\right)^2=25\)
\(\Rightarrow\orbr{\begin{cases}x-1=5\\x-1=-5\end{cases}}\)
\(\Rightarrow\orbr{\begin{cases}x=6\\x=-4\end{cases}}\)
g) \(\left(2x-1\right)^5=x^5\)
\(2x-1=x\)
\(2x-x=1\)
\(x=1\)
