\(2\left(x+5\right)-x^2-5x\)
\(=2\left(x+5\right)-x\left(x+5\right)\)
\(=\left(x+5\right)\left(2-x\right)\)
\(y^2-6y+9-z^2\)
\(=\left(y-3\right)^2-z^2\)
\(=\left(y-3-z\right)\left(y-3+z\right)\)
Bài 1:
c. \(a^3-a^2x-ay+xy\)
\(=a^2\left(a-x\right)-y\left(a-x\right)\)
\(=\left(a-x\right)\left(a^2-y\right)\)
Bài 2:
a. \(x^2-6x=0\)
\(x\left(x-6\right)=0\)
\(\Rightarrow\)\(\orbr{\begin{cases}x=0\\x=6\end{cases}}\)
b) \(x^3-2x2+x=0\)
\(x\left(x^2-3\right)=0\)
\(\Rightarrow\)\(\hept{\begin{cases}x=0\\x^2=3\end{cases}}\)
\(\Rightarrow\)\(\hept{\begin{cases}x=0\\x=\sqrt{3}\\x=-\sqrt{3}\end{cases}}\)
