Đáp án:
$h)(\sqrt{x}+2)(3\sqrt{x}-2)\\ i)\sqrt{x}\left(2\sqrt{x}-3\right)\left(2\sqrt{x}+3\right)\\ k)(2\sqrt{x}-\sqrt{3})(2\sqrt{x}+\sqrt{3})\\ l)(3\sqrt{x}-\sqrt{2})(9x+3\sqrt{2x}+2)$
Giải thích các bước giải:
$h)3x+4\sqrt{x}-4\\ =3x+6\sqrt{x}-2\sqrt{x}-4\\ =3\sqrt{x}(\sqrt{x}+2)-2(\sqrt{x}+2)\\ =(\sqrt{x}+2)(3\sqrt{x}-2)\\ i)4x\sqrt{x}-9\sqrt{x}\\ =\sqrt{x}(4x\sqrt{x}-9)\\ =\sqrt{x}\left((2\sqrt{x})^2-3^2\right)\\ =\sqrt{x}\left(2\sqrt{x}-3\right)\left(2\sqrt{x}+3\right)\\ k)4x-3\\ =(2\sqrt{x})^2-(\sqrt{3})^2\\ =(2\sqrt{x}-\sqrt{3})(2\sqrt{x}+\sqrt{3})\\ l)27x\sqrt{x}-2\sqrt{2}\\ =(3\sqrt{x})^3-\sqrt{2}^3\\ =(3\sqrt{x}-\sqrt{2})(9x+3\sqrt{2x}+2)$