ĐKXĐ: ...
\(\Leftrightarrow x^2-2x+1+2\left(x-1\right)\sqrt{x-1}+x-1=4\)
\(\Leftrightarrow\left(x-1\right)^2+2\left(x-1\right)\sqrt{x-1}+x-1=4\)
\(\Leftrightarrow\left(x-1+\sqrt{x-1}\right)^2=4\)
\(\Leftrightarrow x-1+\sqrt{x-1}=2\)
\(\Leftrightarrow x-1+\sqrt{x-1}-2=0\)
\(\Leftrightarrow\left(\sqrt{x-1}-1\right)\left(\sqrt{x-1}+2\right)=0\)
\(\Leftrightarrow\sqrt{x-1}=1\)
\(\Rightarrow x=2\)
Thu gọn
\(B=\left(\sqrt{x}-1\right)\left(\sqrt{x}+4\right)-\left(\sqrt{x}-3\right)^2+\left(2\sqrt{x}+1\right)^2\)
C = \(\frac{x\sqrt{x}+1}{x-\sqrt{x}+1}+\frac{x-4}{x-2}-\frac{x+2\sqrt{x}+1}{\sqrt{x}+1}\)
\(\dfrac{\sqrt{x-\sqrt{4\left(x-1\right)}}+\sqrt{x+\sqrt{4\left(x-1\right)}}}{\sqrt{x^2-4\left(x-1\right)}}\left(1-\dfrac{1}{x-1}\right)\) (với \(x>1;x\ne2\))
\(\left(\dfrac{4\sqrt{x}}{2+\sqrt{x}}+\dfrac{8}{4-x}\right):\left(\dfrac{\sqrt{x}-1}{x-2\sqrt{x}}-\dfrac{2}{\sqrt{x}}\right)\)
A=\(\left(\frac{\sqrt{x}-1}{x-4}-\frac{\sqrt{x+1}}{x+4\sqrt{x+4}}\right)\):\(\frac{x\sqrt{x}}{\left(4-x\right)^2}\)
B=\(\left(\frac{2\sqrt{x}}{\sqrt{x}-3}-\frac{x+9\sqrt{x}}{x-9}\right):\frac{x\sqrt{x}}{\left(4-x\right)^2}\)
rút gọn các biểu thức
Giải phương trình:
a) \(\sqrt{\left(x-2\right)^2}=\sqrt{x-2}\)
b) \(\sqrt{x^2-1}-\sqrt{x-1}\sqrt{2x+1}=0\)
c) \(\sqrt{9\left(x-1\right)}+\sqrt{4\left(x-1\right)}-\frac{4}{5}\sqrt{25\left(x-1\right)}=1\)
d) \(\sqrt{x}+\frac{16}{\sqrt{x}}=8\)
Rút gọn: A=\(\left(\dfrac{1}{\sqrt{x}-1}+\dfrac{x-\sqrt{x}+1}{x+\sqrt{x}-2}\right):\left(\dfrac{\sqrt{x}+1}{\sqrt{x}+2}-\dfrac{x-\sqrt{x}-4}{x+\sqrt{x}-2}\right)\)
\[D=\left ( \frac{1}{3\sqrt{x}-6} +\frac{1}{x-2\sqrt{x}}\right )\left ( \frac{1}{6} +\frac{1}{2\sqrt{x}}\right )\\ D=\left ( \frac{1}{3\left ( \sqrt{x}-2 \right )} +\frac{1}{\sqrt{x}\left ( \sqrt{x}-2 \right )}\right ).\frac{\sqrt{x}+3}{6\sqrt{x}}\\ D=\frac{\sqrt{x}+3}{3\sqrt{x}\left ( \sqrt{x}-2 \right )}.\frac{\sqrt{x}+3}{6\sqrt{x}}\\ D=\frac{\left ( \sqrt{x}+3 \right )^{2}}{18x\left ( \sqrt{x}-2 \right )}\\ D=\frac{x+6\sqrt{x}+9}{18x\sqrt{x}-36x}\]
A/ Đúng
B/ Sai
Tính:
F= \(\left(\frac{\sqrt{x}}{\sqrt{x}+2}-\frac{x+2}{x-4}\right):\left(\frac{2\sqrt{x}-1}{x-2\sqrt{x}}-\frac{1}{\sqrt{x}}\right)\)
Tìm x biết
1) \(\sqrt{x-1}=3\)
2) \(\sqrt{x}-\sqrt{3}=0\)
3) \(4-5\sqrt{x}=-1\)
4) \(\sqrt{x}\left(\sqrt{ }x-1\right)=0\)
5)\(\left(\sqrt{ }x-2\right)\left(\sqrt{ }x+3\right)=0\)
6) \(\left(\sqrt{ }x+1\right)\left(\sqrt{ }x+2\right)=0\)
7) \(^{^{ }}x2+2\sqrt{2x}+2=1\)
Giải phương trình
\(\frac{3\left(x-\sqrt{3}\right)\left(x-\sqrt{5}\right)}{\left(1-\sqrt{3}\right)\left(1-\sqrt{5}\right)}+\frac{4\left(x-1\right)\left(x-\sqrt{5}\right)}{\left(\sqrt{3}-1\right)\left(\sqrt{3}-\sqrt{5}\right)}+\frac{5\left(x-1\right)\left(x+\sqrt{3}\right)}{\left(\sqrt{5}-1\right)\left(\sqrt{5}-\sqrt{3}\right)}=3x-2\)
