bài 1 rút gọn :
\(\frac{2+\sqrt{5}}{\sqrt{2}+\sqrt{3+\sqrt{5}}}+\frac{2-\sqrt{5}}{\sqrt{2}-\sqrt{3-\sqrt{5}}}\)
bài 3
cho B=\(\frac{2\left(x+4\right)}{x-3\sqrt{x}-4}+\frac{\sqrt{x}}{\sqrt{x}+1}-\frac{8}{\sqrt{x}+4}\) , với x\(\ge\)0, x\(\ne\)16
a) rút gọn
b)tìm x để B\(\in\)Z
Bài 4 cho
C=\(\left(\frac{\sqrt{x}-2}{x-1}-\frac{\sqrt{x}+2}{x+2\sqrt{x}+1}\right)\cdot\left(\frac{\left(1-x\right)^2}{2}\right)\)
a) rút gọn c nếu x\(\ge\)0 , x\(\ne\)1
b) tìm x để C > 0
c) tìm GTLN của C
1.\(\left(\frac{x+2}{x\sqrt{x}-1}+\frac{\sqrt{x}}{x+\sqrt{x}+1}+\frac{1}{1-\sqrt{x}}\right):\frac{\sqrt{x}-1}{2}\)
19.A= \(\left(\frac{1}{\sqrt{x}}-\frac{1}{\sqrt{x}-1}\right):\left(\frac{\sqrt{x}+2}{\sqrt{x}-1}-\frac{\sqrt{x}+1}{\sqrt{x}-2}\right)\)
1,Rút gọn
D=\(\sqrt{20}-\sqrt{45}+3\sqrt{18}+\sqrt{72}\)
2,Rút gọn
M=\(\left(\frac{1}{x-4}-\frac{1}{x+4\sqrt{x}+4}\right)\frac{x+2\sqrt{x}}{\sqrt{x}}\)
Với x>0, x\(\ne\)4
3,Rút gọn
N=\(\left(\frac{3\sqrt{x}+6}{x-4}+\frac{\sqrt{x}}{\sqrt{x}-2}\right):\frac{x-9}{\sqrt{x}-3}\)
Với x>0, x\(\ne\)4, x\(\ne\)9
Giúp mk với, mk đang cần gấp, cảm ơn trước nha
Giải pt \(\frac{1}{\sqrt{x-1}+\sqrt{x-2}}+\frac{1}{\sqrt{x-2}+\sqrt{x-3}}+...+\frac{1}{\sqrt{x-9}+\sqrt{x-10}}=1\)
22.\(A=\left(\frac{x}{\sqrt{x}-1}-\sqrt{x}\right):\left(\frac{\sqrt{x}+1}{\sqrt{x}}-\frac{1}{1-\sqrt{x}}+\frac{2-x}{x-\sqrt{x}}\right)\)
12.\(A=\left(\frac{x}{\sqrt{x}-1}-\sqrt{x}\right):\left(\frac{\sqrt{x}+1}{\sqrt{x}}-\frac{1}{1-\sqrt{x}}+\frac{2-x}{x-\sqrt{x}}\right)\)
10. A=\(\frac{x^2-\sqrt{x}}{x+\sqrt{x}+1}-\frac{2x+\sqrt{x}}{\sqrt{x}}+\frac{2\left(x-1\right)}{\sqrt{x}-1}\)
11.A=\(\left(\frac{2\sqrt{x}+1}{x\sqrt{x}-1}-\frac{1}{\sqrt{x}-1}\right):\left(\frac{\sqrt{x}+2}{x+\sqrt{x}+1}\right)\)