a. Ta có: Q(x)-H(x)=\(\left(2x^2-2x-1\right)-\left(x^2-2x\right)\)
= \(2x^2-2x-1-x^2+2x\)
= \(x^2-1\)
b. Ta có: H(x)=\(x^2-2x=0\)
=\(x.\left(x-2\right)=0\)
\(\Rightarrow\left[{}\begin{matrix}x=0\\x-2=0\end{matrix}\right.\) \(\Rightarrow\left[{}\begin{matrix}x=0\\x=2\end{matrix}\right.\)
a. Ta có: Q(x)-H(x)=(2x2−2x−1)−(x2−2x)(2x2−2x−1)−(x2−2x)
= 2x2−2x−1−x2+2x2x2−2x−1−x2+2x
= x2−1x2−1
b. Ta có: H(x)=x2−2x=0x2−2x=0
=x.(x−2)=0x.(x−2)=0
⇒[x=0x−2=0⇒[x=0x−2=0 ⇒[x=0x=2
