Question

 

a,\(\sqrt{5x-2}\)

\(b,\sqrt{\dfrac{3x-1}{5}}\)

\(c,\sqrt{\dfrac{3}{15-2x}}\)

\(d,\sqrt{\dfrac{-2x}{x^2-3x+9}}\)

Tính

Answer 1

`sqrt{5x-2}`

`Đ k : 5x-2 >= 0`

`=> 5x >= 2 => x > 2/5`

`sqrt{(3x-1)/5}`

`Đk : 3x-1 >= 0`

`=> 3x >= 1 => x>=1/3`

`sqrt{3/(15-2x)}`

Đk : 15 -2x > 0`

`=> 2x < 15`

`=> x >15/2`

 

Answer 2

a: ĐKXĐ: 5x-2>=0

=>x>=2/5

b: ĐKXĐ: 3x-1>=0

=>x>=1/3

c: ĐKXĐ: 15-2x>0

=>x<15/2