a/ ( x - 1 )4 = 81
( x - 1)4 = 34
=> x - 1 = 3
x = 3 + 1
x = 4
b/ ( 3x - 2 )2 = 1
( 3x - 2)2 = 12
=> 3x - 2 = 1
3x = 1 + 2
3x = 3
x = 3 : 3
x = 1
c/ ( x - 1 )5 = -32
( x - 1 )5 = (-2)5
=> x - 1 = -2
x = -2 + 1
x = -1
d/ ( 2x - 3 )3 = 125
( 2x - 3 )3 = 53
=> 2x - 3 = 5
2x = 5 + 3
2x = 8
x = 8 : 2
x = 4
k nha bn !!!!
\(\left(x-1\right)^4=81\)
\(\Rightarrow\left(x-1\right)=3\)
\(\Rightarrow x=4\)
\(\left(3x-2\right)^2=1\)
\(\Rightarrow\orbr{\begin{cases}3x-2=-1\\3x-2=1\end{cases}\Rightarrow\orbr{\begin{cases}x=\frac{1}{3}\\x=1\end{cases}}}\)
a) (x-1)4=34
x-1 =3
x=3+1=4
b) (3x-2)2=12
3x-2=1
3x=1+2
3x=3
x=3:3
x=1
c)(x-1)5=-25
x-1=-2
x=-2+1
x=-1
(2x-3)3=53
2x-3=5
2x=5+3
2x=8
x=8:2
x=4
a \(\left(x-1\right)^4=81< =>\orbr{\begin{cases}\left(x-1\right)^4=3^4\\\left(x-1\right)^4=\left(-3\right)^4\end{cases}}< =>\) \(\orbr{\begin{cases}x-1=3\\x-1=-3\end{cases}}\)<=> \(\orbr{\begin{cases}x=4\\x=-2\end{cases}}\) b\(\left(3x-2\right)^2=1=>\left(3x-2\right)^2=1^2< =>\) \(\orbr{\begin{cases}3x-2=1\\3x-2=-1\end{cases}< =>\orbr{\begin{cases}3x=3\\3x=-1\end{cases}}}< =>\orbr{\begin{cases}x=1\\x=\frac{-1}{3}\end{cases}}\)
c\(\left(x-1\right)^5=-32< =>\left(x-1\right)^5=\left(-2\right)^5< =>x-1=-2\)\(< =>x=-1\) d \(\left(2x-3\right)^3=125< =>\left(2x-3\right)^3=5^3\) \(< =>2x-3=5< =>2x=8< =>x=4\) nhớ vs nha
a) \(\left(x-1\right)^4=81\)
\(\Leftrightarrow\left(x-1\right)^4=\left(\pm3\right)^4\)
\(\Leftrightarrow\orbr{\begin{cases}x-1=3\\x-1=-3\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}x=4\\x=-2\end{cases}}\)
\(\left(3x-2\right)^2=1\)
\(\Leftrightarrow\left(3x-2\right)^2=\left(\pm1\right)^2\)
\(\Leftrightarrow\orbr{\begin{cases}3x-2=1\\3x-2=-1\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}3x=3\\3x=1\end{cases}}\)
\(\Leftrightarrow\orbr{\begin{cases}x=1\\x=\frac{1}{3}\end{cases}}\)