a) M = \(\dfrac{\left(\sqrt{x}+1\right)^2-\left(\sqrt{x}-1\right)^2}{\left(\sqrt{x}+1\right)\left(\sqrt{x}-1\right)}\). \(\dfrac{x-\sqrt{x}}{x}\) ( x>0)
M = \(\dfrac{4\sqrt{x}}{\left(\sqrt{x}+1\right)\left(\sqrt{x}-1\right)}\). \(\dfrac{\sqrt{x}\left(\sqrt{x}-1\right)}{x}\)
M = \(\dfrac{4}{\sqrt{x}+1}\)
b) M>1 => 4 > \(\sqrt{x}\) + 1 > 0
=> 3 > \(\sqrt{x}\) > -1
=> 9>x>0
Đúng thì like giúp mik nha bạn. Thx