Câu hỏi của Anh Thị Tuyết Ngân

Question

Tìm x ϵ Q:a) ( x - $\frac{1}{2}$ )2 =0                             b) (x - 2)21                    c) (2x - 1)3 = -8                     d) (x + $\frac{1}{2}$)2= $\frac{1}{16}$Chứng minh rằng 10...

Edowa Conan · Accepted Answer

a)$\left(x-\frac{1}{2}\right)^2=0$   $x-\frac{1}{2}=0$   $x=\frac{1}{2}$Vậy $x=\frac{1}{2}$b)(x-2)2=1    (x-2)2=12=(-1)2$\Rightarrow\left[\begin{array}{nghiempt}x-2=1\x-2=-1\end{array}\right.$$\Rightarrow\left[\begin{array}{nghiempt}x=3\x=1\end{array}\right.$Vậy x=3;1Câu trả lời: a)$\left(x-\frac{1}{2}\right)^2=0$   $x-\frac{1}{2}=0$   $x=\frac{1}{2}$Vậy $x=\frac{1}{2}$b)(x-2)2=1    (x-2)2=12=(-1)2$\Rightarrow\left[\begin{array}{nghiempt}x-2=1\x-2=-1\end{array}\right.$$\Rightarrow\left[\begin{array}{nghiempt}x=3\x=1\end{array}\right.$Vậy x=3;1

Trần Việt Linh · Answer

a) $\left(x-\frac{1}{2}\right)^2=0$$\Leftrightarrow x-\frac{1}{2}=0\Leftrightarrow x=\frac{1}{2}$b) $\left(x-2\right)^2=1$$\Leftrightarrow\left[\begin{array}{nghiempt}x-2=1\x-2=-1\end{array}\right.$$\Leftrightarrow\left[\begin{array}{nghiempt}x=3\x=1\end{array}\right.$c) $\left(2x-1\right)^3=-8$$\Leftrightarrow2x-1=-2\Leftrightarrow2x=-1\Leftrightarrow x=-\frac{1}{2}$d) $\left(x+\frac{1}{2}\right)^2=\frac{1}{16}$ $\Leftrightarrow\left[\begin{array}{nghiempt}x+\frac{1}{2}=\frac{1}{4}\x+\frac{1}{2}=-\frac{1}{4}\end{array}\right.$$\Leftrightarrow\left[\begin{array}{nghiempt}x=-\frac{1}{4}\x=-\frac{3}{4}\end{array}\right.$ Câu trả lời: a) $\left(x-\frac{1}{2}\right)^2=0$$\Leftrightarrow x-\frac{1}{2}=0\Leftrightarrow x=\frac{1}{2}$b) $\left(x-2\right)^2=1$$\Leftrightarrow\left[\begin{array}{nghiempt}x-2=1\x-2=-1\end{array}\right.$$\Leftrightarrow\left[\begin{array}{nghiempt}x=3\x=1\end{array}\right.$c) $\left(2x-1\right)^3=-8$$\Leftrightarrow2x-1=-2\Leftrightarrow2x=-1\Leftrightarrow x=-\frac{1}{2}$d) $\left(x+\frac{1}{2}\right)^2=\frac{1}{16}$ $\Leftrightarrow\left[\begin{array}{nghiempt}x+\frac{1}{2}=\frac{1}{4}\x+\frac{1}{2}=-\frac{1}{4}\end{array}\right.$$\Leftrightarrow\left[\begin{array}{nghiempt}x=-\frac{1}{4}\x=-\frac{3}{4}\end{array}\right.$

Nguyễn Huy Tú · Answer

a) $\left(x-\frac{1}{2}\right)^2=0$$\Rightarrow x-\frac{1}{2}=0$$\Rightarrow x=\frac{1}{2}$ Vậy $x=\frac{1}{2}$b) $\left(x-2\right)^2=1$$\Rightarrow\left(x-2\right)^2=1^2$$\Rightarrow x-2=1$ hoặc $x-2=-1$+) $x-2=1\Rightarrow x=3$+) $x-2=-1\Rightarrow x=1$Vậy $x=3$ hoặc x = 1c) $\left(2x-1\right)^3=-8$$\Rightarrow\left(2x-1\right)^3=\left(-2\right)^3$$\Rightarrow2x-1=-2$$\Rightarrow2x=-1$$\Rightarrow x=\frac{-1}{2}$Vậy $x=\frac{-1}{2}$d) $\left(x+\frac{1}{2}\right)^2=\frac{1}{16}$$\Rightarrow\left(x+\frac{1}{2}\right)^2=\left(\frac{1}{4}\right)^2$$\Rightarrow x+\frac{1}{2}=\frac{1}{4}$ hoặc $x+\frac{1}{2}=\frac{-1}{4}$+) $x+\frac{1}{2}=\frac{1}{4}\Rightarrow x=\frac{-1}{4}$+) $x+\frac{1}{2}=\frac{-1}{4}\Rightarrow x=\frac{-3}{4}$Vậy $x=\frac{-1}{4}$ hoặc $x=\frac{-3}{4}$Câu trả lời: a) $\left(x-\frac{1}{2}\right)^2=0$$\Rightarrow x-\frac{1}{2}=0$$\Rightarrow x=\frac{1}{2}$ Vậy $x=\frac{1}{2}$b) $\left(x-2\right)^2=1$$\Rightarrow\left(x-2\right)^2=1^2$$\Rightarrow x-2=1$ hoặc $x-2=-1$+) $x-2=1\Rightarrow x=3$+) $x-2=-1\Rightarrow x=1$Vậy $x=3$ hoặc x = 1c) $\left(2x-1\right)^3=-8$$\Rightarrow\left(2x-1\right)^3=\left(-2\right)^3$$\Rightarrow2x-1=-2$$\Rightarrow2x=-1$$\Rightarrow x=\frac{-1}{2}$Vậy $x=\frac{-1}{2}$d) $\left(x+\frac{1}{2}\right)^2=\frac{1}{16}$$\Rightarrow\left(x+\frac{1}{2}\right)^2=\left(\frac{1}{4}\right)^2$$\Rightarrow x+\frac{1}{2}=\frac{1}{4}$ hoặc $x+\frac{1}{2}=\frac{-1}{4}$+) $x+\frac{1}{2}=\frac{1}{4}\Rightarrow x=\frac{-1}{4}$+) $x+\frac{1}{2}=\frac{-1}{4}\Rightarrow x=\frac{-3}{4}$Vậy $x=\frac{-1}{4}$ hoặc $x=\frac{-3}{4}$

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