Mong lần sau bạn dùng latex nhoa <3
a)
P = ($\frac{1}{x-√x}$ + $\frac{√x}{x-1}$) : $\frac{x√x-1}{x√x-√x}$
= [$\frac{1}{√x(√x - 1)}$ + $\frac{√x}{(√x-1)(√x+1)}$] : $\frac{(√x-1)(x + √x + 1)}{√x(√x-1)(√x+1)}$
= $\frac{x + √x + 1}{(√x(√x-1)(√x+1)}$ . $\frac{√x(√x+1)}{x + √x + 1}$
= $\frac{1}{√x-1}$
b)
Để P = $\frac{1}{2}$
⇔ $\frac{1}{√x-1}$ = $\frac{1}{2}$
⇒ √x - 1 = 2
⇔ √x = 3
⇔ x = 9 (TMĐK)
Vậy x = 9 thì P = $\frac{1}{2}$