1) x - 2 = 0
\(x=0+2\)
\(x=2\)
2) (x-4) (x+4) - x(x - 3) = -1
\(\left(x^2-4^2\right)-\left(x^2+3x\right)=-1\)
\(-4^2+3x=-1\)
\(16+3x=-1\)
\(3x=-17\)
\(x=-17:3\)
\(\Rightarrow x=-\dfrac{17}{3}\)
3) x3 - 9x = 0
\(\Rightarrow x\left(x^2-9\right)=0\)
\(\Rightarrow\left\{{}\begin{matrix}x=0\\x^2-9=0\end{matrix}\right.\)
\(\Rightarrow\left\{{}\begin{matrix}x=0\\x^2=9\end{matrix}\right.\)
\(\Rightarrow\left\{{}\begin{matrix}x=0\\x=3\end{matrix}\right.\)
x - 2 = 0
=> x = 2
(x - 4)(x + 4) - x(x - 3) = -1
(x2 - 16) - x2 + 3x = -1
x2 - 16 - x2 + 3x = -1
-16 + 3x = -1
3x = 15
=> x = 5
c) 5(x - 2) - x + 2 = 0
5(x - 2) - (x - 2) = 0
(5 - 1)(x - 2) = 0
4(x - 2) = 0
=> x - 2 = 0
=> x = 2
x3 - 9x = 0
x(x2 - 9) = 0
x(x - 3)(x + 3) = 0
\(\Rightarrow\left\{{}\begin{matrix}x=0\\x-3=0\\x+3=0\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x=0\\x=3\\x=-3\end{matrix}\right.\)
vậy x3 - 9x = 0 <=> x = 0 hoặc x = 3 hoặc x = -3
tik mik nha PLEASE
