Question

Tìm x biết :

(4x - 15 )²⁰¹⁶  = (4x-15)²⁰¹⁵

Answer 1

Answer 2

\(\left(4x-15\right)^{2016}=\left(4x-15\right)^{2015}\\ \Leftrightarrow\left[{}\begin{matrix}4x-15=0\\4x-15=1\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}4x=15\\4x=16\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=\dfrac{15}{4}\\x=4\end{matrix}\right.\)

Vậy \(x\in\left\{\dfrac{15}{4};4\right\}\)