Đáp án:
Giải thích các bước giải:
x(x+3)=0
⇒\(\left[ \begin{array}{l}x=0\\x+3=0\end{array} \right.\)
⇒\(\left[ \begin{array}{l}x=0\\x=0-3\end{array} \right.\)
⇒\(\left[ \begin{array}{l}x=0\\x=-3\end{array} \right.\)
(x-2)(5-x)=0
⇒\(\left[ \begin{array}{l}x-2=0\\5-x=0\end{array} \right.\)
⇒\(\left[ \begin{array}{l}x=0+2\\x=5-0\end{array} \right.\)
⇒\(\left[ \begin{array}{l}x=2\\x=5\end{array} \right.\)
(x-1)(x²+1)=0
⇒\(\left[ \begin{array}{l}x-1=0\\x^2+1=0\end{array} \right.\)
⇒\(\left[ \begin{array}{l}x=0+1\\x=0-1\end{array} \right.\)
⇒\(\left[ \begin{array}{l}x=-1\\x^2=-1\end{array} \right.\)
⇒\(\left[ \begin{array}{l}x=-1\\x^2=-1^2\end{array} \right.\)
⇒\(\left[ \begin{array}{l}x=-1\\x=-1\end{array} \right.\)
