\(\frac{8\sqrt{x}-x-31}{-x+8\sqrt{x}-15}-\frac{\sqrt{x}+5}{\sqrt{x}-3}-\frac{3\sqrt{x}-1}{5-\sqrt{x}}\)
Rút gọn?
Tìm GTNN của \(D=\frac{5\sqrt{x}-5x-8}{\left(\sqrt{x}-1\right)\left(\sqrt{x}+3\right)}\)
1) rút gọn biểu thức sau :
a) \(\dfrac{x+2\sqrt{x}-3}{\sqrt{x}-1}\) b) \(\dfrac{4y+3\sqrt{y}-7}{4\sqrt{y}+7}\) c ) \(\dfrac{x\sqrt{y}-y\sqrt{x}}{\sqrt{x}-\sqrt{y}}\)
d) \(\dfrac{x-3\sqrt{x}-4}{x-\sqrt{x}-12}\) e) \(\dfrac{1+\sqrt{x}+\sqrt{y}+\sqrt{xy}}{1+\sqrt{y}}\) ( với x>0 , y>0 )
f) \(\sqrt{8-2\sqrt{15}}+\sqrt{5}+\sqrt{3}\) g) \(\sqrt{9-2\sqrt{4}}-\sqrt{9+2\sqrt{14}}\)
1) \(\sqrt{x-1}=\sqrt{2x+3}\)
2) \(\sqrt{2x-3}=\sqrt{x-1}\)
3) \(\sqrt{2-x}=\sqrt{3+x}\)
4) \(\sqrt{4x-8}=2\sqrt{x-2}\)
5) \(\sqrt{x^2-5}\sqrt{4x-9}\)
6) \(\sqrt{x-2}=\sqrt{x^2-2x}\)
7) \(\sqrt{x^2-3x}=\sqrt{15-5x}\)
8) \(\sqrt{4x^2-9}=\sqrt{-20-18}\)
Có điều kiện cho từng câu hộ mình nhé!!!
9) \(\sqrt{x-2}=\sqrt{x-2}\)
câu 1 rút gọn
A=\(\dfrac{\sqrt{2}-\sqrt{3}}{\sqrt{2}+\sqrt{3}}+\dfrac{\sqrt{2}+\sqrt{3}}{\sqrt{3}-\sqrt{2}}\)
B=\(\dfrac{2}{\sqrt{3}-\sqrt{5}}+\dfrac{3-2\sqrt{3}}{\sqrt{3}-2}\)
C = \(\dfrac{\sqrt{2}+1}{\sqrt{5+2\sqrt{6}}}+\dfrac{2}{\sqrt{8}+2\sqrt{15}}\)
Câu 2 cho pt
B= \(\left(\dfrac{\sqrt{x}-1}{\sqrt{x}+1}-\dfrac{\sqrt{x}+1}{\sqrt{x}-1}\right):\dfrac{\sqrt{x}}{\sqrt{x}+1}\)
a, tìm ĐKXĐ và rút gọn
b, tính B khi x =\(3+2\sqrt{2}\)
c, tìm x để B nguyên
Cho biểu thức \(A=\left(\frac{x-5\sqrt{x}}{x-25}-1\right):\left(\frac{25-x}{x+2\sqrt{x}-15}-\frac{\sqrt{x}+3}{\sqrt{x}+5}+\frac{\sqrt{x}-5}{\sqrt{x}-3}\right)\)
a)Rút gọn
b)Với \(x\ge0,x\ne25,x\ne9\).Tìm GTNN của \(B=\frac{A\left(x+16\right)}{5}\)
\(\left(\dfrac{x-5\sqrt{x}}{x-25}-1\right):\left(\dfrac{25-x}{x+2\sqrt{x}-15}-\dfrac{\sqrt{x}+3}{\sqrt{x}+5}+\dfrac{\sqrt{x}-5}{\sqrt{x}-3}\right)\)
Tìm GTNN
P=\(\sqrt{x+1}\)-\(\sqrt{x-8}\)
Giai phuong trinh \(\sqrt{x^3+15}+2=\sqrt{x^3+8}+3x\)