Question

Answer 1

Bài 2:

a) ĐKXĐ: \(x\ge2\)

\(bpt\Leftrightarrow\sqrt{x-2}\le3\)

\(\Leftrightarrow0\le x-2\le9\)

\(\Leftrightarrow2\le x\le11\)

b) ĐKXĐ: \(x\le2\)

\(pt\Leftrightarrow\sqrt{2-x}+2\sqrt{2-x}=3\)

\(\Leftrightarrow3\sqrt{2-x}=3\Leftrightarrow\sqrt{2-x}=1\)

\(\Leftrightarrow2-x=1\Leftrightarrow x=1\left(tm\right)\)

c) Thiếu đề

d) ĐKXĐ: \(1\ge x\ge\dfrac{1}{2}\)

\(pt\Leftrightarrow2x-1=1-x\)

\(\Leftrightarrow3x=2\Leftrightarrow x=\dfrac{2}{3}\left(tm\right)\)

Bài 3:

a) \(\sqrt{7}+\sqrt{15}< \sqrt{9}+\sqrt{16}=3+4=7\)

b) \(\sqrt[3]{125}=\sqrt[3]{5^3}=5\)