b) (0,5 - x)2 - 3 = 0 ⇔ 0,52 + x2 - 2.0,5x - 3 = 0
⇔ x2 + 0,25 - x - 3 = 0
⇔ x2 - x - 2,75 = 0
⇔ ????
c: \(\Leftrightarrow\left(2x-3\sqrt{2}\right)\left(2x+\sqrt{2}\right)=0\)
hay \(x\in\left\{\dfrac{3\sqrt{2}}{2};-\dfrac{\sqrt{2}}{2}\right\}\)
b) (0,5 - x)2 - 3 = 0 ⇔ 0,52 + x2 - 2.0,5x - 3 = 0
⇔ x2 + 0,25 - x - 3 = 0
⇔ x2 - x - 2,75 = 0
⇔ ????
c: \(\Leftrightarrow\left(2x-3\sqrt{2}\right)\left(2x+\sqrt{2}\right)=0\)
hay \(x\in\left\{\dfrac{3\sqrt{2}}{2};-\dfrac{\sqrt{2}}{2}\right\}\)
Giải các hệ phương trình sau
a,\(\left\{{}\begin{matrix}\sqrt{3}x-y=\sqrt{2}\\x-\sqrt{2}y=\sqrt{3}\end{matrix}\right.\)
b, \(\left\{{}\begin{matrix}5\left(x-y\right)-3\left(2x+3y\right)=12\\3\left(x+2y\right)-4\left(x+2y\right)=5\end{matrix}\right.\)
c, \(\left\{{}\begin{matrix}\dfrac{x+2}{y-1}=\dfrac{x-4}{y+2}\\\dfrac{2x+3}{y-1}=\dfrac{4x+1}{2y+1}\end{matrix}\right.\)
Giải hệ phương trình: \(\left\{{}\begin{matrix}\left(\sqrt{2}-1\right)x+\left(\sqrt{2}+1\right)y=3\sqrt{2}-1\\\left(\sqrt{2}+1\right)x+\left(\sqrt{2}-1\right)y=3\sqrt{2}+1\end{matrix}\right.\)
Giải hệ phương trình:
1. \(\left\{{}\begin{matrix}3\sqrt{x}-\sqrt{y}=5\\2\sqrt{x}+3\sqrt{y}=18\end{matrix}\right.\)
2. \(\left\{{}\begin{matrix}\sqrt{x+3}-2\sqrt{y+1}=2\\2\sqrt{x+3}+\sqrt{y+1}=4\end{matrix}\right.\)
3. \(\left\{{}\begin{matrix}3\sqrt{x}+2\sqrt{y}=6\\\sqrt{x}-\sqrt{y}=4,5\end{matrix}\right.\)
4. \(\left\{{}\begin{matrix}\sqrt{x}+\sqrt{y+1}=1\\\sqrt{y}+\sqrt{x+1}=1\end{matrix}\right.\)
giải pt:
a, \(\sqrt{x-2}+\sqrt{y+1995}+\sqrt{z-1996}=\dfrac{1}{2}\left(x+y+z\right)\)
b\(\sqrt{3x^2-6x+19}+\sqrt{x^2-2x+26}=8-x^2+2x\)
c,\(\left(\sqrt{x+8}-\sqrt{x+3}\right)\left(\sqrt{x^2+11x+24}+1\right)=5\)
giúp tôi giải bài này với thank nhiều
giải hệ phương trình:
a,\(\left\{{}\begin{matrix}\dfrac{1}{2}\left(x+2\right)\left(y+3\right)=\dfrac{1}{2}xy+50\\\dfrac{1}{2}\left(x-2\right)\left(y-2\right)=\dfrac{1}{2}xy-32\end{matrix}\right.\)
b,\(\left\{{}\begin{matrix}\dfrac{-1}{2}x+\dfrac{1}{3}y=0\\y-x=1\end{matrix}\right.\)
c,\(\left\{{}\begin{matrix}x\left(y-2\right)=\left(x+2\right)\left(y-4\right)\\\left(x-3\right)\left(2y+7\right)=\left(2x-7\right)\left(y+3\right)\end{matrix}\right.\)
Giải hệ phương trình:
1. \(\left\{{}\begin{matrix}\sqrt{x}+2\sqrt{-1}=5\\4\sqrt{x}-\sqrt{y-1}=2\end{matrix}\right.\)
2. \(\left\{{}\begin{matrix}\sqrt{3x-1}-\sqrt{2y+1}=1\\2\sqrt{3x-1}+3\sqrt{2y+1}=12\end{matrix}\right.\)
3. \(\left\{{}\begin{matrix}\sqrt{x-2}+\sqrt{y-3}=3\\2\sqrt{x-2}-3\sqrt{y-3}=-4\end{matrix}\right.\)
4. \(\left\{{}\begin{matrix}2\sqrt{x+1}-3\sqrt{-2}=5\\4\sqrt{x+1}+\sqrt{y-2}=17\end{matrix}\right.\)
giải phương trình
\(\left(2x^2-3x+1\right)\left(2x^2-3x-9\right)=-9\)
Tìm m đề phương trình \(x^2-2x-2m+1=0\) có 2 nghiệm thỏa mãn \(x^2^{_2}\left(x^2^{_1}-1\right)+x^{2_1}\left(x^{2_2}-1\right)=8\)
(4) cmr: pt sau luôn có nghiệm ∀m
a) \(x^2+2\left(m-1\right)x-2m-3=0\)
b) \(x^2+\left(2m-1\right)x+2m-2=0\)
c) \(x^2-2\left(m+1\right)+2m-2=0\)
d) \(x^2-2\left(m+1\right)x+2m=0\)
e) \(x^2-2mx+m-7=0\)
f) \(x^2-2\left(m-1\right)x-3-m=0\)
giúp mk vs ạ mk cần gấp