a)Mũ ba hai vế ta được: $12-x+14+x+3\sqrt[3]{(12-x)(14+x)}(\sqrt[3]{12-x}+\sqrt[3]{14+x})=8$$\Leftrightarrow 2+3.2\sqrt[3]{(12-x)(14+x)}=8\Leftrightarrow \sqrt[3]{(12-x)(14+x)}=1$$\Leftrightarrow -x^{2}-2x+168=1\Leftrightarrow x^{2}+2x-167=0\Rightarrow x=-1+2\sqrt{42}$ hoặc $x=-1-2\sqrt{42}$b)CMTT nha
a)Mũ ba hai vế ta được: $12-x+14+x+3\sqrt[3]{(12-x)(14+x)}(\sqrt[3]{12-x}+\sqrt[3]{14+x})=8$$\Leftrightarrow 2+3.2\sqrt[3]{(12-x)(14+x)}=8\Leftrightarrow \sqrt[3]{(12-x)(14+x)}=1$$\Leftrightarrow -x^{2}-2x+168=1\Leftrightarrow x^{2}+2x-167=0\Rightarrow x=-1+2\sqrt{42}$ hoặc $x=-1-2\sqrt{42}$
a)Mũ ba hai vế ta được: $12-x+14+x+3\sqrt[3]{(12-x)(14+x)}(\sqrt[3]{12-x}+\sqrt[3]{14+x})=8$$\Leftrightarrow 2+3.2\sqrt[3]{(12-x)(14+x)}=8\Leftrightarrow \sqrt[3]{(12-x)(14+x)}=1$$\Leftrightarrow -x^{2}-2x+168=1\Leftrightarrow x^{2}+2x-167=0\Rightarrow x=-1+2\sqrt{42}$ hoặc $x=-1-2\sqrt{42}$
b)CMTT nha