Question

Tìm n biết:

\(3^{\left(n+2\right)\left(n-1\right)}=1\)

Answer 1

\(3^{\left(n+2\right)\left(n-1\right)}=1\)

\(\Leftrightarrow3^{\left(n+2\right)\left(n-1\right)}=3^0\)

\(\Leftrightarrow\left(n+2\right)\left(n-1\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}n+2=0\\n-1=0\end{matrix}\right.\) \(\Leftrightarrow\left[{}\begin{matrix}n=-2\\n=1\end{matrix}\right.\)

Vậy ..

Answer 2

\(3^{\left(n+2\right)\left(n-1\right)}=1\Leftrightarrow\left(n+2\right)\left(n-1\right)=0\Leftrightarrow\left[{}\begin{matrix}n=-2\\n=1\end{matrix}\right.\)

Answer 3

3^{(n + 2)(n - 1)} = 1

⇔ 3^{(n + 2)(n - 1)} = 3⁰

⇔ (n + 2)(n - 1) = 0

⇔ \(\left[{}\begin{matrix}n+2=0\\n-1=0\end{matrix}\right.\)

⇔ \(\left[{}\begin{matrix}n=-2\\n=1\end{matrix}\right.\)