\(\left|x^2-\left(2x+3\right)\right|\le\left|x^2\right|+\left|2x+3\right|=x^2+\left|2x+3\right|\)
Dấu "=" xảy ra khi và chỉ khi \(x^2\left(2x+3\right)\le0\Rightarrow\left[{}\begin{matrix}x=0\\x\le-\frac{3}{2}\end{matrix}\right.\)
Vậy nghiệm của pt là \(\left[{}\begin{matrix}x=0\\x\le-\frac{3}{2}\end{matrix}\right.\)
GPT
a,\(\left\{{}\begin{matrix}x^3=5x+y\\y^3=5y+x\end{matrix}\right.\)
b,\(\left\{{}\begin{matrix}x^2-2y^2=2x+y\\y^2-2x^2=2y+x\end{matrix}\right.\)
Gpt \(\left(3x+1\right)\sqrt{x^2+3}=3x^2+2x+3\)
Giải các phương trình sau :
1. \(x^4-7x^3+6x^2+14x+4=0\)
2. \(2\left(2x^2+3x+3\right)^2+6x^2+8x+12=0\)
3. \(\left(2x^2-5x+1\right)^2-10x^2+24x-4=0\)
4. \(\left(2x+1\right)\left(2x-3\right)\left(2x-2\right)\left(2x+6\right)=100\)
5. \(\left(2x+1\right)\left(2x-3\right)\left(2x-2\right)\left(2x+6\right)=\left(x+6\right)^2\)
\(\left(x^2-5x+3\right)\left(2x^2-5x+1\right)=\left(x^2+5x+3\right)\left(2x^2-5x-1\right)\)
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)\(\left\{{}\begin{matrix}x^3+2x^2=x^2y+2xy\\2\sqrt{x^2-2y-1}+\sqrt[3]{y^3-14=x-2}\end{matrix}\right.\)
giải pt
a) \(x^2+4x-3\left|x+2\right|+4=0\)
b) \(\left(x+2\right)^2-3\left|x+2\right|-4=0\)
c) \(\left(x^2-3\right)^2-6\left|x^2-3\right|+5=0\)
d) \(\frac{x^2-4x+4}{x^2-2x+1}+\frac{\left|2x-4\right|}{x-1}=3\)
e) \(\left|\frac{2x-1}{x+2}\right|-2\left|\frac{x+2}{2x-1}\right|=1\)
f) \(x^2+\frac{1}{x^2}-10=2\left|x-\frac{1}{x}\right|\)
1)2x(25x-4)-(5x-2)(5x+1)=8 / 5)\(2\left(x-2\right)-3\left(3x-1\right)=\left(x-3\right)\)
2)x(4x-3)-(2x-2)(2x-1)=5 / 6)\(\frac{2}{x+1}-\frac{1}{x-2}=\frac{3x-11}{\left(x+1\right)\left(x-2\right)}\)
3)\(\frac{5}{2x+3}+\frac{3}{9-x^2}=\frac{8}{7\left(x=3\right)}\) / 7)\(\frac{5x-2}{6}+\frac{3-4x}{2}=2-\frac{x+7}{3}\)
4)\(\frac{2}{3\left(x-2\right)}+\frac{5}{12-3x^2}=\frac{3}{4\left(x+2\right)}\) / 8)\(\frac{2}{x+1}-\frac{1}{x-2}=\frac{3x-11}{\left(x+1\right)\left(x-2\right)}\)
Giải hệ
a) \(\left\{{}\begin{matrix}x^2\left(y^2+1\right)+2y\left(x^2+x+1\right)=3\\\left(x^2+x\right)\left(y^2+y\right)=1\end{matrix}\right.\)
b) \(\left\{{}\begin{matrix}\left(6x+5\right)\sqrt{2x+1}-2y-3y^3=0\\y+\sqrt{x}=\sqrt{2x^2+4x-23}\end{matrix}\right.\)
Giải bất pt
\(\dfrac{9}{\left|x-5\right|-3}\ge\left|x-2\right|\)
