Sửa lại đề bài cho mk là: \(\sqrt{2x+3+\sqrt{x+2}}+\sqrt{2x+2-\sqrt{x+2}}=1+2\sqrt{x+2}\)

Ta có: \(\sqrt{x^2+2x+3}+\sqrt{x^2+x+2}=2x+2\)

Bình phương 2 vế ta có:

\(2\sqrt{\left(x^2+2x+3\right)\left(x^2+x+2\right)}=4\left(x+1\right)^2-x^2-2x-3-x^2-x-2\) (\(x\ge-1\))

\(\Leftrightarrow2\sqrt{\left(x^2+2x+3\right)\left(x^2+x+2\right)}=4x^2+8x+4-2x^2-3x-5\)

\(\Leftrightarrow2\sqrt{\left(x^2+2x+3\right)\left(x^2+x+2\right)}=2x^2+5x-1\)​\(\Leftrightarrow2\sqrt{\left(x^2+2x+3\right)\left(x^2+x+2\right)}=2x^2+5x-1\)​

Bình phương 2 vế, ta được:

\(4\left(x^2+2x+3\right)\left(x^2+x+2\right)=\left(2x^2+5x-1\right)^2\) ( ĐK:\(\left[{}\begin{matrix}x\le\dfrac{-5-\sqrt{33}}{4}\\x\ge\dfrac{-5+\sqrt{33}}{4}\end{matrix}\right.\))

\(\Leftrightarrow4\left(x^4+x^3+2x^2+2x^3+2x^2+4x+3x^2+3x+6\right)=4x^4+20x^3+21x^2-10x+1\)

\(\Leftrightarrow4x^4+4x^3+8x^2+8x^3+8x^2+16x+12x^2+12x+24=4x^4+20x^3+21x^2-10x+1\)\(\Leftrightarrow-8x^3+7x^2+38x+23=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{23}{8}\\x=-1\left(loai\right)\end{matrix}\right.\)

Vậy nghiệm của PT là \(x=\dfrac{23}{8}\)

Đặt \(\sqrt{x^2+2x+3}=a;\sqrt{x^2+x+2}=b\) ĐK : \(a;b>0\)

PT <=> a + b = 2(a² - b²) 

<=> a + b = 2(a - b)(a + b)

<=> (a + b)(2a - 2b - 1) = 0

<=> \(\left[{}\begin{matrix}a+b=0\\2a=2b+1\end{matrix}\right.\Leftrightarrow2a=2b+1\left(\text{vì a ; b > 0}\right)\)

Khi đó \(2\sqrt{x^2+2x+3}=2\sqrt{x^2+x+2}+1\)

\(\Leftrightarrow4\left(x^2+2x+3\right)=4\left(x^2+x+2\right)+4\sqrt{x^2+x+2}+1\)

<=> \(4\sqrt{x^2+x+2}=4x+3\)

\(\Leftrightarrow\left\{{}\begin{matrix}16\left(x^2+x+2\right)=16x^2+24x+9\\x\ge-\dfrac{3}{4}\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}8x=23\\x\ge-\dfrac{3}{4}\end{matrix}\right.\Leftrightarrow x=\dfrac{23}{8}\)

ĐK: `{(2x^2+8x+6>=0),(x^2-1>=0),(2x+2>=0):} <=> {(x=-1),(x>=1):}`

`\sqrt(2x^2+8x+6)+\sqrt(x^2-1)=2x+2`

`<=>(2x^2+8x+6)+(x^2-1)+2\sqrt((2x^2+8x+6)(x^2-1))=(2x+2)^2`

`<=>2(x+3)(x+1)+(x-1)(x+2)+2\sqrt((x+1)^2 (x+3)(x-1))=4(x+1)^2`

`<=> (x+1)[2(x+3)+(x-1)+2\sqrt((x+3)(x-1))-4(x+1)]=0`

`<=> [(x=-1\ (TM)),([2(x+3)+(x-1)+2\sqrt((x+3)(x-1))-4(x+1)]=0\ (1)):}`

(1) `<=> x-1=2\sqrt((x+3)(x-1))`

`<=>x^2-2x+1=4(x+3)(x-1)`

`<=>x=1\ `(TM)

Vậy `S={\pm 1}`.

\(ĐK:x\le-3;x\ge-1\)

\(PT\Leftrightarrow\sqrt{2\left(x+1\right)\left(x+3\right)}+\sqrt{\left(x-1\right)\left(x+1\right)}-2\left(x+1\right)=0\\ \Leftrightarrow\sqrt{x+1}\left(\sqrt{2\left(x+3\right)}+\sqrt{x-1}-2\sqrt{x+1}\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x+1=0\\\sqrt{2\left(x+3\right)}+\sqrt{x-1}-2\sqrt{x+1}=0\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=-1\left(tm\right)\\\sqrt{2\left(x+3\right)}+\sqrt{x-1}=2\sqrt{x+1}\left(1\right)\end{matrix}\right.\)

\(\left(1\right)\Leftrightarrow2\left(x+3\right)+\left(x-1\right)+2\sqrt{2\left(x+3\right)\left(x-1\right)}=4\left(x+1\right)\\ \Leftrightarrow2\sqrt{2\left(x+3\right)\left(x-1\right)}=x-1\\ \Leftrightarrow8\left(x+3\right)\left(x-1\right)-\left(x-1\right)^2=0\\ \Leftrightarrow\left(x-1\right)\left(7x+25\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x=1\left(tm\right)\\x=-\dfrac{25}{7}\left(ktm\right)\end{matrix}\right.\Leftrightarrow x=1\)

Vậy \(S=\left\{-1;1\right\}\)

\(ĐK:\left\{{}\begin{matrix}x\le\dfrac{1}{2};4\le x\\\dfrac{1}{2}\le x\\x\le-11;\dfrac{1}{2}\le x\end{matrix}\right.\Leftrightarrow x\le-11;4\le x\)

\(PT\Leftrightarrow\sqrt{\left(x-4\right)\left(2x-1\right)}+3\sqrt{2x-1}-\sqrt{\left(2x-1\right)\left(x+11\right)}=0\\ \Leftrightarrow\sqrt{2x-1}\left(\sqrt{x-4}-\sqrt{x+11}+3\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}2x-1=0\\\sqrt{x-4}-\sqrt{x+11}=-3\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=\dfrac{1}{2}\left(tm\right)\\x-4+x+11-2\sqrt{x^2+7x-44}=9\left(1\right)\end{matrix}\right.\)

\(\left(1\right)\Leftrightarrow2\sqrt{x^2+7x-44}=2x-2\\ \Leftrightarrow\sqrt{x^2+7x-44}=x-1\\ \Leftrightarrow x^2+7x-44=x^2-2x+1\\ \Leftrightarrow9x=45\Leftrightarrow x=5\left(tm\right)\)

Vậy \(S=\left\{\dfrac{1}{2};5\right\}\)

https://hoc24.vn/cau-hoi/giai-pt-sqrt2x2-9x43sqrt2x-1sqrt2x221x-11.2005877637936

làm r nha :vv

ĐKXĐ: \(x\ge\dfrac{5}{2}\)

\(\sqrt{2x-4+2\sqrt{2x-5}}+\sqrt{2x+4+6\sqrt{2x-5}}=14\)

\(\Leftrightarrow\sqrt{\left(\sqrt{2x-5}+1\right)^2}+\sqrt{\left(\sqrt{2x-5}+3\right)^2}=14\)

\(\Leftrightarrow\left|\sqrt{2x-5}+1\right|+\left|\sqrt{2x-3}+3\right|=14\)

\(\Leftrightarrow2\sqrt{2x-5}=10\)

\(\Leftrightarrow\sqrt{2x-5}=5\)

\(\Leftrightarrow2x-5=25\)

\(\Leftrightarrow x=15\)