Question

Tìm x \(\in\) Z

a, x.(x+3)=0

b, (x-2).(5-x)=0

c, (x-10).(x²+1)=0

Answer 1

\(x\left(x+3\right)=0\)

=> \(\left\{\begin{matrix}x=0\\x+3=0\end{matrix}\right.\Rightarrow\left\{\begin{matrix}x=0\\x=-3\end{matrix}\right.\)

Vậy x = 0 hoặc -3

\(\left(x-2\right)\left(5-x\right)=0\)

\(\Rightarrow\left\{\begin{matrix}x-2=0\\5-x=0\end{matrix}\right.\Rightarrow\left\{\begin{matrix}x=2\\x=5\end{matrix}\right.\)

Vậy x = 2 hoặc 5

\(\left(x-10\right)\left(x^2+1\right)=0\)

\(\Rightarrow\left\{\begin{matrix}x-10=0\\x^2+1=0\end{matrix}\right.\Rightarrow\left\{\begin{matrix}x=10\\x^2=-1\end{matrix}\right.\)

\(\Rightarrow\left\{\begin{matrix}x=10\\x=-1\end{matrix}\right.\)

Vậy x = 10 hoặc -1

Answer 2

a) x=-3, x=0

b) x=2, x=5

c) x=10

Answer 3

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