Đáp án+Giải thích các bước giải:
e,
`3x+\sqrt{4x^2-12x+9}=4(x≤\frac{4}{3})`
`⇔\sqrt{(2x-3)^2}=4-3x`
`⇔|2x-3|=4-3x`
$⇔\left[\begin{matrix}2x-3=4-3x\\2x-3=3x-4\end{matrix}\right.$
$⇔\left[\begin{matrix}2x+3x=4+3\\3x-2x=-3+4\end{matrix}\right.$
$⇔\left[\begin{matrix}5x=7\\x=1(tm)\end{matrix}\right.$
$⇔\left[\begin{matrix}x=\dfrac{7}{5}(L)\\x=1\end{matrix}\right.$
Vậy `S={1}`
g,
`x^2+4\sqrt{3}x=1-4\sqrt{3}`
`⇔x^2+4\sqrt{3}x+4\sqrt{3}-1=0`
`⇔(x+2\sqrt{3})^2-(13-4\sqrt{3})=0`
`⇔(x+2\sqrt{3}+2\sqrt{3}-1)(x+2\sqrt{3}-2\sqrt{3}+1)=0`
`⇔(x+4\sqrt{3}-1)(x+1)=0`
$⇔\left[\begin{matrix}x+4\sqrt{3}-1=0\\x+1=0\end{matrix}\right.$
$⇔\left[\begin{matrix}x=1-4\sqrt{3}\\x=-1\end{matrix}\right.$
Vậy `S={1-4\sqrt{3};-1}`
