Question

bài 50 giải phương trình

a) \(\sqrt{2x}-3\sqrt{8x}+4\sqrt{32x}=52\)

b)\(3\sqrt{x-1}+2\sqrt{4x-4}-3\sqrt{9x-9}+6=0\)

Answer 1

a) \(\sqrt{2x}\) - \(6\sqrt{2x}\) + \(16\sqrt{2x}\) = 52 <=> \(11\sqrt{2x}\) = 52 <=> \(\sqrt{2x}\) =\(\dfrac{52}{11}\) <=> 2x = \(\dfrac{2704}{121}\) <=> x = \(\dfrac{1352}{121}\)

b) \(3\sqrt{x-1}\) + \(4\sqrt{x-1}\) - \(9\sqrt{x-1}\) + 6 =0 <=> \(-2\sqrt{x-1}\) = -6 <=> \(\sqrt{x-1}\) = 3 <=> x-1 =9 <=> x= 10