Question

Tìm x biết \(a\ge3;b\ge2\)

a)\(\sqrt{x^2-4x+4}=3\)

b)\(\sqrt{x^2-12}=2\)

c)\(\sqrt{x+3}=x+3\)

d)\(\sqrt{x^{ }-2x+1}=x-1\)

g)\(\sqrt{x^2-4-x^2+4}=0\)

h)\(\sqrt{x^2-9}+\sqrt{x^2-6x+9}=0\)

Answer 1

a) \(\sqrt{x^2-4x+4}=\sqrt{\left(x-2\right)^2}=3\Leftrightarrow x-2=3\Leftrightarrow x=5\)

b) \(\sqrt{x^2-12}=2\) \(\Leftrightarrow x^2-12=4\Leftrightarrow x^2=16\Leftrightarrow x=\pm4\)

c) \(\sqrt{x+3}=x+3\Leftrightarrow x+3-\sqrt{x+3}=0\)

\(\Leftrightarrow\sqrt{x+3}\left(\sqrt{x+3}-1\right)=0\Leftrightarrow\left[{}\begin{matrix}x+3=0\\x+3=1\end{matrix}\right.\) \(\Leftrightarrow\left[{}\begin{matrix}x=-3\\x=-2\end{matrix}\right.\)

mấy câu còn lại bn làm tương tự

Answer 2

Mysterious Person Akai Haruma

Answer 3

d: =>|x-1|=x-1

=>x-1>=0

=>x>=1

h: \(\Leftrightarrow\sqrt{\left(x-3\right)\left(x+3\right)}+\sqrt{\left(x-3\right)^2}=0\)

=>x-3=0

=>x=3