Question

Giải:

1)a) \(17\sqrt{3x-1}=3x\)

b) \(\sqrt{2+\sqrt{3x-5}}=\sqrt{x+1}\)

c)\(\sqrt{\dfrac{5x+7}{x+3}}=4\)

2)Giai pt :

a) x+y+12=\(4\sqrt{x}+6\sqrt{y}-1\)

b) \(\sqrt{x-a}+\sqrt{y-b}+\sqrt{z-c}=\dfrac{1}{2}\left(x+y+z\right)\)

c)\(\sqrt{x+\sqrt{14x-4y}}+\sqrt{x-\sqrt{14x-4y}}=\sqrt{14}\)

d)x-\(4\sqrt{2x+2}-2\sqrt{2-x+9}=0\)

Answer 1

Bài 1: 

b: \(\Leftrightarrow2+\sqrt{3x-5}=x+1\)

\(\Leftrightarrow\sqrt{3x-5}=x-1\)

\(\Leftrightarrow\left\{{}\begin{matrix}x^2-2x+1=3x-5\\x>=1\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}x^2-5x+6=0\\x>=1\end{matrix}\right.\Leftrightarrow x\in\left\{2;3\right\}\)

c: \(\Leftrightarrow5x+7=16\left(x+3\right)\)

=>16x+48=5x+7

=>11x=-41

hay x=-41/11