Question

tìm x biết:

\(x^2-x-\frac34\)

Answer 1

không bít

Answer 2

     \(x^2-x-\frac{3}{4}=0\)

\(\Rightarrow x^2+\frac{1}{2}x-\frac{3}{2}x-\frac{3}{4}=0\)

\(\Rightarrow x\left(x+\frac{1}{2}\right)-\frac{3}{2}\left(x+\frac{1}{2}\right)=0\)

\(\Rightarrow\left(x-\frac{3}{2}\right)\left(x+\frac{1}{2}\right)=0\)

\(\Rightarrow\hept{\begin{cases}x-\frac{3}{2}=0\\x+\frac{1}{2}=0\end{cases}\Rightarrow\hept{\begin{cases}x=\frac{3}{2}\\x=-\frac{1}{2}\end{cases}}}\)

Chúc bạn học tốt.