Question

Giúp em bài 7i) với ạ em cảm ơn

Answer 1

i: Ta có: \(\sqrt{x^2-x+\dfrac{1}{4}}=\dfrac{15}{2}\)

\(\Leftrightarrow\left|x-\dfrac{1}{2}\right|=\dfrac{15}{2}\)

\(\Leftrightarrow\left[{}\begin{matrix}x-\dfrac{1}{2}=\dfrac{15}{2}\\x-\dfrac{1}{2}=-\dfrac{15}{2}\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=8\\x=-7\end{matrix}\right.\)