Giải hệ phương trình:

1. \(\left\{{}\begin{matrix}x+3=2\sqrt{\left(3y-x\right)\left(y+1\right)}\\\sqrt{3y-2}-\sqrt{\dfrac{x+5}{2}}=xy-2y-2\end{matrix}\right.\)

2. \(\left\{{}\begin{matrix}\sqrt{2y^2-7y+10-x\left(y+3\right)}+\sqrt{y+1}=x+1\\\sqrt{y+1}+\dfrac{3}{x+1}=x+2y\end{matrix}\right.\)

3. \(\left\{{}\begin{matrix}\sqrt{4x-y}-\sqrt{3y-4x}=1\\2\sqrt{3y-4x}+y\left(5x-y\right)=x\left(4x+y\right)-1\end{matrix}\right.\)

4. \(\left\{{}\begin{matrix}9\sqrt{\dfrac{41}{2}\left(x^2+\dfrac{1}{2x+y}\right)}=3+40x\\x^2+5xy+6y=4y^2+9x+9\end{matrix}\right.\)

5. \(\left\{{}\begin{matrix}\sqrt{xy+\left(x-y\right)\left(\sqrt{xy}-2\right)}+\sqrt{x}=y+\sqrt{y}\\\left(x+1\right)\left[y+\sqrt{xy}+x\left(1-x\right)\right]=4\end{matrix}\right.\)

6. \(\left\{{}\begin{matrix}x^4-x^3+3x^2-4y-1=0\\\sqrt{\dfrac{x^2+4y^2}{2}}+\sqrt{\dfrac{x^2+2xy+4y^2}{3}}=x+2y\end{matrix}\right.\)

7. \(\left\{{}\begin{matrix}x^3-12z^2+48z-64=0\\y^3-12x^2+48x-64=0\\z^3-12y^2+48y-64=0\end{matrix}\right.\)

Mình rút gọn như thế này đúng không nhỉ?

\(P=\left(2-\frac{\sqrt{x}-1}{2\sqrt{x}-3}\right):\left(\frac{6\sqrt{x}+1}{2x-\sqrt{x}-3}+\frac{\sqrt{x}}{\sqrt{x}+1}\right)\)

\(P=\left[\frac{2\left(2\sqrt{x}-3\right)}{2\sqrt{x}-3}-\frac{\sqrt{x}-1}{2\sqrt{x}-3}\right]:\left[\frac{6\sqrt{x}+1}{\left(\sqrt{x}+1\right)\left(2\sqrt{x}-3\right)}+\frac{\sqrt{x}\left(2\sqrt{x}-3\right)}{\left(\sqrt{x}+1\right)\left(2\sqrt{x}-3\right)}\right]\)

\(P=\left(\frac{4\sqrt{x}-6}{2\sqrt{x}-3}-\frac{\sqrt{x}-1}{2\sqrt{x}-3}\right):\left(\frac{6\sqrt{x}+1}{\left(\sqrt{x}+1\right)\left(2\sqrt{x}-3\right)}+\frac{2x-3\sqrt{x}}{\left(\sqrt{x}+1\right)\left(2\sqrt{x}-3\right)}\right)\)

\(P=\left(\frac{4\sqrt{x}-6-\sqrt{x}+1}{2\sqrt{x}-3}\right):\left(\frac{6\sqrt{x}+1+2x-3\sqrt{x}}{\left(\sqrt{x}+1\right)\left(2\sqrt{x}-3\right)}\right)\)

\(P=\frac{3\sqrt{x}-5}{2\sqrt{x}-3}:\frac{2x+3\sqrt{x}+1}{\left(\sqrt{x}+1\right)\left(2\sqrt{x}-3\right)}\)

\(P=\frac{3\sqrt{x}-5}{2\sqrt{x}-3}.\frac{\left(\sqrt{x}+1\right)\left(2\sqrt{x}-3\right)}{2x+3\sqrt{x}+1}\)

\(P=\left(3\sqrt{x}-5\right).\frac{\left(\sqrt{x}+1\right)}{2x+3\sqrt{x}+1}\)

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

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

1)\(\begin{cases}x^2-y\left(x+y\right)+1=0\\\left(x^2+1\right)\left(x+y-2\right)+y=0\end{cases}\)

2)\(\begin{cases}x^2-4x+y^4+4y^2=2\\xy^2+2y^2+6x=23\end{cases}\)

3)\(\begin{cases}2x+\frac{1}{x+y}=3\\4x^2+4y^2+4xy+\frac{3}{\left(x+y\right)^2}=7\end{cases}\)

4)\(\begin{cases}y^6+x^9+3y^4+3y^2=8\\4y^2-3x^3y^2+x^3=2\end{cases}\)

5)\(\begin{cases}\sqrt{x+y}-2\sqrt{x-y}=1\\x+\sqrt{x^2+y^2}=8\end{cases}\)

6) \(\begin{cases}x+y-2=\frac{y}{x^2+1}\\x^2+y^2+xy=y-1\end{cases}\)

7) \(\begin{cases}4x-1=\sqrt{\left(2x+y\right).\left(2y+1\right)}\\\sqrt{x+2y+1}-\sqrt{x+y-1}=\sqrt{x-1}\end{cases}\)

8) \(\begin{cases}\left(x+y\right).\left(x+4y^2+y\right)+3y^4=0\\\sqrt{x+2y^2+1}-y^2+y+1=0\end{cases}\)

1)\(\begin{cases}\sqrt{4x^2+\left(4x-9\right)\left(x-3y\right)}+\sqrt{3xy}=9y\\4\sqrt{\left(x+2\right)\left(3y+2x\right)}=3x+9\end{cases}\)                                              4)\(\begin{cases}\left(x^2+y\right)\sqrt{x-y+6}=2x^2-x+3y-2\\\sqrt{10x-xy-12}+1=\frac{y-x}{\sqrt{y-4}+\sqrt{6-x}}\end{cases}\)

2)\(\begin{cases}x^2+\left(y-6\right)^2=y+13x+27\\\sqrt{9x^2+\left(2x-3\right)\left(x-y\right)}+4\sqrt{xy}=7y\end{cases}\)                                                 5)\(\begin{cases}\sqrt{4xy+\left(3\sqrt{xy}-7\right)\left(x-y\right)}+2\sqrt{xy}=4y\\\left(2x+1\right)\left[12y-1+9\sqrt{xy}-x^2-x\right]=27\left(x+1\right)\end{cases}\)

3)\(\begin{cases}\sqrt{\left(x+2\right)\left(y+1\right)+\left(x-y+1\right)\sqrt{y^2+1}}+\sqrt{x+2}=y+\sqrt{y+1}+1\\\sqrt{3x+1}-\sqrt{y+1}=2x^2+4x-y-1\end{cases}\)

giải giúp mik bt này vs mn!

1)\(\left\{{}\begin{matrix}2x^2+y^2+x=3\left(xy+1\right)+2y\\\dfrac{2}{3+\sqrt{2x-y}}+\dfrac{2}{3+\sqrt{4-5x}}=\dfrac{9}{2x-y+9}\end{matrix}\right.\)

2)\(\left\{{}\begin{matrix}\left(x+3y+1\right)\sqrt{2xy+2y}=y\left(3x+4y+3\right)\\\left(\sqrt{x+3}-\sqrt{2y-2}\right)\left(x-3+\sqrt{x^2+x+2y-4}\right)=4\end{matrix}\right.\)

3)\(\left\{{}\begin{matrix}x-\dfrac{1}{x}=y-\dfrac{1}{y}\\2y=x^3+1\end{matrix}\right.\)

4)\(\left\{{}\begin{matrix}\sqrt{2x-3}=\left(y^2+2011\right)\left(5-y\right)+\sqrt{y}\\y\left(y-x+2\right)=3x+3\end{matrix}\right.\)

5)\(\left\{{}\begin{matrix}x^3+2x^2=x^2y+2xy\\2\sqrt{x^2-2y-1}+\sqrt[3]{y^3-14=x-2}\end{matrix}\right.\)

Câu 1:Chứng minh với mọi \(x\ge0;x\ne4\)thì biểu thức Q=\(\frac{\sqrt{x}+2}{\sqrt{x+4}}\)không thể nhận giá trị nguyên

Câu 2:Giải các phương trình sau:

a)\(4x^2+11x+18=8\sqrt{\left(x+2\right)\left(x^2+2x+3\right)}\)

b)\(3x^2-11x-22=7\sqrt{\left(x+2\right)\left(x+5\right)\left(x-7\right)}\)

Câu 3:Giải các hệ phương trình:

a)\(\left\{{}\begin{matrix}\left(x-y\right)\left(x^2+y^2\right)+y\left(x^2-5\right)=xy^2-5x\\4x\sqrt{y+3}+2\sqrt{2x-1}=4y^2+3x+3\end{matrix}\right.\)

b)\(\left\{{}\begin{matrix}\sqrt{2x+1}.\left(2x+3\right)-2y=y^3\\\sqrt{2x+13}+5=3y+\sqrt{2x+6}\end{matrix}\right.\)

Câu 4:Giả sử (x;y) là các số thực thỏa mãn:

\(\left(x+\sqrt{3+x^2}\right).\left(y+\sqrt{3+y^2}\right)=9\)

Tìm giá trị nhỏ nhất của biểu thức \(P=x^2+xy+y^2\)

Giải hệ:

\(\left\{{}\begin{matrix}x^2+y^2+xy=5\\27x^3+6y^2x=2+y^3+30x^2y\end{matrix}\right.\)

\(\left\{{}\begin{matrix}x^2+y^2+\frac{8xy}{x+y}=16\\\frac{x^2}{8y}+\frac{2x}{3}=\sqrt{\frac{x^3}{3y}+\frac{x^2}{4}}-\frac{y}{2}\end{matrix}\right.\), \(\left\{{}\begin{matrix}\frac{1}{3x}+\frac{2x}{3y}=\frac{x+\sqrt{y}}{2x^2+y}\\2\left(2x+\sqrt{y}\right)=\sqrt{2x+6}-y\end{matrix}\right.\)

\(\left\{{}\begin{matrix}x^2y-3x-1=3x\sqrt{y}\left(\sqrt{1-x}-1\right)^3\\\sqrt{8x^2-3xy+4y^2}+\sqrt{xy}=4y\end{matrix}\right.\)

Cho các số a,b,c là các số k âm sao cho tổng hai số bất kì đều dương.CMR \(\sqrt{\frac{a}{b+c}}+\sqrt{\frac{b}{c+a}}+\sqrt{\frac{c}{a+b}}+\frac{16\sqrt{ab+bc+ac}}{a+b+c}\ge8\)