\(=\dfrac{\left(\sqrt{x}-2\right)\left(\sqrt{x}+2\right)}{\sqrt{x}+2}+\dfrac{\sqrt{x}\left(\sqrt{x}+3\right)}{\sqrt{x}}\)
=\(\sqrt{x}-2+\sqrt{x}+3=2\sqrt{x}+1\)
a.(2x^2+x+1)(2x^2+x-4)=-4
b.(x-3)(x-2)(x+1)(x+2)=60
c.(x+2)^4+(x+4)^4=16
Thu gọn biểu thức
A=\(\sqrt{\dfrac{3\sqrt{3}}{2\sqrt{3}+1}}-\sqrt{\dfrac{\sqrt{3}+4}{5-2\sqrt{3}}}\)
B=\(\dfrac{x\sqrt{x}-2x+28}{x-3\sqrt{x}-4}-\dfrac{\sqrt{x}-4}{\sqrt{x}+1}+\dfrac{\sqrt{x}+8}{4-\sqrt{x}}\left(x\ge0,x\ne16\right)\)
\(\left(\frac{2+\sqrt{x}}{2-\sqrt{x}}-\frac{4x}{x-4}-\frac{2-\sqrt{x}}{2+\sqrt{x}}\right):\frac{4\sqrt{x^3-12\sqrt{x}}}{2x-\sqrt{x^3}}\)
\(\left(\dfrac{x-2\sqrt{x}}{x-4}-1\right):\left(\dfrac{4-x}{x-\sqrt{x}-6}-\dfrac{\sqrt{x}-2}{3-\sqrt{x}}-\dfrac{\sqrt{x}-3}{\sqrt{x}+2}\right)\)
voi x\(\ge0,x\ne4;9\)
Rút gọn
\(\dfrac{x^3-3x+\left(x^2-1\right)\sqrt{x^2-4}-2}{x^3-3x+\left(x^2-1\right)\sqrt{x^2-4}+2}\) với x>2
1.cho biểu thức A=\(\dfrac{\sqrt{x}+2}{\sqrt{x}+3}-\dfrac{5}{x+\sqrt{x}-6}-\dfrac{1}{\sqrt{x}-2}\)với(x≥0;x≠4)
a)rút gọn A
b)tính A khi x=6+4\(\sqrt{2}\)
2.cho biểu thức P=\(\left(\dfrac{4\sqrt{x}}{\sqrt{x}+2}-\dfrac{8x}{x-4}\right):\left(\dfrac{\sqrt{x}+2}{\sqrt{x}-2}+3\right)\)với x≥0;x≠1;x≠4
a)rút gọn P
b)tìm x để P=-4
chứng minh rằng
a, \(\frac{2+\sqrt{3}}{2+\sqrt{4+2\sqrt{3}}}+\frac{2-\sqrt{3}}{2-\sqrt{4-2\sqrt{3}}}=1\)
b, \(\frac{1}{x+\sqrt{x}}+\frac{2\sqrt{x}}{x-1}-\frac{1}{x-\sqrt{x}}=\frac{2}{\sqrt[]{x}}\)
giải các phương trình sau:
a. \(\sqrt{x-2}=x-4\)
b.\(\sqrt{x-4}=4-x\)
c.\(\sqrt{x^2-2x+2}=x-1\)
d.\(\sqrt{x^2-2x+1}+\sqrt{x^2+4x+4}=3\)
đ.\(2\sqrt{2x+3}=x^2+4x+5\)
e.\(\sqrt{x^2-2x+5}=x^2-2x-1\)
f.\(\sqrt{x+3}=3-\sqrt{x}\)
g.\(\sqrt{4x^2+9x+5}=\sqrt{x^2-1}+\sqrt{2x^2+x-1}\)
h.\(x+\sqrt{x+\frac{1}{2}+\sqrt{x+\frac{1}{4}}}=2\)
Cho \(P=\dfrac{3x-2\sqrt{x}-4}{x+\sqrt{x}-2}-\dfrac{\sqrt{x}+1}{\sqrt{x}+2}-\dfrac{2\sqrt{x}+2}{\sqrt{x}-1}\)
a, Rút gọn P.
b, Tính P khi \(x=4+2\sqrt{3}\)
c, Tìm xϵZ để PϵZ
