Tìm x sao cho \(f\left( x \right) - g\left( x \right) + h\left( x \right) = 0\)

* Hướng dẫn giải

\(\begin{array}{l}\,f\left( x \right) - g\left( x \right) + h\left( x \right) = 0\\ \Leftrightarrow 2x + 1 = 0\\ \Leftrightarrow 2x\,\,\,\,\,\,\,\, =  - 1\\ \Leftrightarrow \,\,\,\,x\,\,\,\,\,\,\,\, = \frac{{ - 1}}{2}\end{array}\)

Vậy  \(x = \frac{{ - 1}}{2}\)

Chọn C