Câu hỏi của anh trần

Question

$\left(\dfrac{3\sqrt{2}+\sqrt{6}}{\sqrt{12}+2}-\dfrac{\sqrt{54}}{3}\right).\dfrac{a}{\sqrt{6}}=-1$

Bùi Nhất Duy · Accepted Answer

$\left(\dfrac{3\sqrt{2}+6}{\sqrt{12}+2}-\dfrac{\sqrt{54}}{3}\right).\dfrac{a}{3}=-1$

$\Leftrightarrow\left[\dfrac{\sqrt{6}\left(\sqrt{3}+1\right)}{2\left(\sqrt{3}+1\right)}-\dfrac{3\sqrt{6}}{3}\right].\dfrac{a}{\sqrt{6}}=-1$

$\Leftrightarrow\left(\dfrac{\sqrt{6}}{2}-\sqrt{6}\right).\dfrac{a}{\sqrt{6}}=-1$

$\Leftrightarrow\sqrt{6}\left(\dfrac{1}{2}-1\right).\dfrac{a}{\sqrt{6}}=-1$

$\Leftrightarrow-\dfrac{1}{2}.a=-1$

$\Leftrightarrow a=2$

Vậy a=2Câu trả lời: $\left(\dfrac{3\sqrt{2}+6}{\sqrt{12}+2}-\dfrac{\sqrt{54}}{3}\right).\dfrac{a}{3}=-1$

$\Leftrightarrow\left[\dfrac{\sqrt{6}\left(\sqrt{3}+1\right)}{2\left(\sqrt{3}+1\right)}-\dfrac{3\sqrt{6}}{3}\right].\dfrac{a}{\sqrt{6}}=-1$

$\Leftrightarrow\left(\dfrac{\sqrt{6}}{2}-\sqrt{6}\right).\dfrac{a}{\sqrt{6}}=-1$

$\Leftrightarrow\sqrt{6}\left(\dfrac{1}{2}-1\right).\dfrac{a}{\sqrt{6}}=-1$

$\Leftrightarrow-\dfrac{1}{2}.a=-1$

$\Leftrightarrow a=2$

Vậy a=2

Bài 1: Căn bậc hai