Question

tìm nghiệm của mỗi đa thức sau a) (x-4)(1-x)

2x^2-6x

 

Answer 1

a.Giả sử \(=0\)

\(\Rightarrow\left(x-4\right)\left(1-x\right)=0\)

\(\rightarrow\left[{}\begin{matrix}x-4=0\\1-x=0\end{matrix}\right.\) \(\rightarrow\left[{}\begin{matrix}x=4\\x=1\end{matrix}\right.\)

b.Giả sử \(=0\)

\(\Rightarrow2x^2-6x=0\)

\(2x\left(x-3\right)=0\)

\(\rightarrow\left[{}\begin{matrix}2x=0\\x-3=0\end{matrix}\right.\) \(\rightarrow\left[{}\begin{matrix}x=0\\x=3\end{matrix}\right.\)

Answer 2

a) \(\left(x-4\right)\left(1-x\right)=0=>\left[{}\begin{matrix}x-4=0\\1-x=0\end{matrix}\right.=>\left[{}\begin{matrix}x=4\\x=1\end{matrix}\right.\)

b)\(2x^2-6x=0=>x\left(2x-6\right)=0\)

\(=>\left[{}\begin{matrix}x=0\\2x=6\end{matrix}\right.=>\left[{}\begin{matrix}x=0\\x=3\end{matrix}\right.\)