Question

giup minh cau nay voi

Answer 1

`1)\sqrt{50}-3\sqrt{8}+\sqrt{32}=5\sqrt{2}-6\sqrt{2}+4\sqrt{2}=3\sqrt{2}`

`2)`

`a)\sqrt{x^2-4x+4}=1`

`<=>\sqrt(x-2)^2}=1`

`<=>|x-2|=1`

`<=>[(x-2=1),(x-2=-1):}<=>[(x=3),(x=1):}`

`b)\sqrt{x^2-3x}-\sqrt{x-3}=0`              `ĐK: x >= 3`

`<=>\sqrt{x}\sqrt{x-3}-\sqrt{x-3}=0`

`<=>\sqrt{x-3}(\sqrt{x}-1)=0`

`<=>[(\sqrt{x-3}=0),(\sqrt{x}-1=0):}`

`<=>[(x-3=0),(\sqrt{x}=1):}<=>[(x=3(t//m)),(x=1(ko t//m)):}`