a/ PT <=> (x2 - 6x + 9) + (x - \(\sqrt{3x}\)) + (3 - \(\sqrt{3x}\)) = 0
<=> (\(\sqrt{x}-\sqrt{3}\))(\(\sqrt{3}x+x\sqrt{x}-3\sqrt{x}-3\sqrt{3}\)) + √x(\(\sqrt{x}-\sqrt{3}\)) + \(\sqrt{3}\left(\sqrt{3}-\sqrt{x}\right)\)= 0
<=> x = 3
b/ bình phương 2 vế ta có
x4 - 83 + 16x2 - 64x + 64 = 0
<=> (x2 + 8)(x2 - 8x + 8) = 0
<=> x = \(4\:+\:2\sqrt{2}\)