Question

giải phương trình sqrt(x - 2) - sqrt(4x - 8) - 1/2 * sqrt(9x - 18) = 2

Answer 1

`sqrt(x - 2) - sqrt(4x - 8) - 1/2 * sqrt(9x - 18) = 2`

`Đk :x >=2`

`<=>sqrt(x - 2) -2sqrt(x - 2) -3/2sqrt(x - 2) =2`

`<=> -5/2 sqrt(x - 2) =2`

`<=> sqrt(x - 2) =-4/5 (vô-lí)`

Vậy PT vô nghiệm :`S=∅`