Giải phương trình:
1) \(x^4-2\sqrt{3}x^2+x+3-\sqrt{3}=0\)
2)\(\dfrac{1}{1+\sqrt{2x^2+1}}\)+\(\dfrac{\sqrt{x^2+1}}{1+\sqrt{x^2+1}}\)-\(\dfrac{32}{\sqrt{2\sqrt{2x^2+1}\left(1+\sqrt{2x^2+1}\right)+2\sqrt{\dfrac{1}{x^2+1}}\left(1+\sqrt{\dfrac{1}{x^2+1}}\right)+8}}\)= -7
3)\(2x^2\left(x-1\right)+x=\left(x-1\right)\sqrt{2x\left(x^2-x+2\right)}+6\)
Rút gọn:
\(M=1-\left[\dfrac{2x-1+\sqrt{x}}{1-x}+\dfrac{2x\sqrt{x}+x-\sqrt{x}}{1+x\sqrt{x}}\right]\cdot\left[\dfrac{\left(x-\sqrt{x}\right)\left(1-\sqrt{x}\right)}{2\sqrt{x}-1}\right]\)
Giải::
ĐK: x khác +- 1
\(M=1-\left[\dfrac{\left(\sqrt{x}-\dfrac{1}{2}\right)\left(\sqrt{x}+1\right)}{\left(1+\sqrt{x}\right)\left(1-\sqrt{x}\right)}+\dfrac{\sqrt{x}\left(\sqrt{x}-\dfrac{1}{2}\right)\left(\sqrt{x}+1\right)}{\left(1+\sqrt{x}\right)\left(1-\sqrt{x}+x\right)}\right]\cdot\left[\dfrac{-\sqrt{x}\left(1-\sqrt{x}\right)^2}{2\left(\sqrt{x}-\dfrac{1}{2}\right)}\right]\)
\(=1-\left[\dfrac{\left(\sqrt{x}-\dfrac{1}{2}\right)}{\left(1-\sqrt{x}\right)}\cdot\dfrac{-\sqrt{x}\left(1-\sqrt{x}\right)^2}{2\left(\sqrt{x}-\dfrac{1}{2}\right)}+\dfrac{\sqrt{x}\left(\sqrt{x}-\dfrac{1}{2}\right)}{1-\sqrt{x}+x}\cdot\dfrac{-\sqrt{x}\left(1-\sqrt{x}\right)^2}{2\left(\sqrt{x}-\dfrac{1}{2}\right)}\right]\)
\(=1-\left[\dfrac{-\sqrt{x}\left(1-\sqrt{x}\right)}{2}+\dfrac{-x\left(1-\sqrt{x}\right)^2}{2\left(1-\sqrt{x}+x\right)}\right]\)
rồi làm sao nữa ak?? Tớ có quy đồng lên, tính sơ sơ rồi nhưng thấy kq không gọn.
Câu b là : tìm các số nguyên x để M cũng là số nguyên . Nên tớ nghĩ kq sẽ gọn.
NHỜ MẤY CAO NHÂN RA TAY GIÚP VỚI NHAK ^^!
\(\left(\dfrac{2x+1}{\sqrt{x^3-1}}-\dfrac{\sqrt{x}}{x+\sqrt{x+1}}\right)\left(\dfrac{1+\sqrt{x^3}}{1+\sqrt{x}}-\sqrt{x}\right)\)
\(\dfrac{\sqrt{x-2\sqrt{x-1}+}\sqrt{x+2\sqrt{x-1}}}{\sqrt{\dfrac{1}{x^2}-\dfrac{2}{x}+1}}\)
\(\left(\dfrac{x\sqrt{x}+y\sqrt{y}}{\sqrt{x}+\sqrt{y}}-\sqrt{xy}\right):\left(x-y\right)+\dfrac{2\sqrt{y}}{\sqrt{x}+\sqrt{y}}\)
\(\left(\dfrac{\sqrt{x}}{3+\sqrt{x}}+\dfrac{x+9}{9-x}\right):\left(\dfrac{3\sqrt{x}+1}{x-3\sqrt{x}}-\dfrac{1}{\sqrt{x}}\right)\)
Mí bạn giải giúp mik bài này nhé!:))))))))))))))))))))))))))))))ARIGATO MÍ BẠN NHIW!!!!!!!!!!:)))))))))))))))))))))))))))))))))
Chứng minh biểu thức không phụ thuộc biến:
\(\dfrac{2x}{\left(\sqrt{x}+1\right)\left(\sqrt{x}+2\right)}+\dfrac{5\sqrt{x}}{\left(\sqrt{x}+1\right)\left(\sqrt{x}+3\right)}+\dfrac{\sqrt{x}+10}{\left(\sqrt{x}+2\right)\left(\sqrt{x}+3\right)}\) (x >/0)
Rút gọn biểu thức:
E=\(\left(\dfrac{2x\sqrt{x}+x-\sqrt{x}}{x\sqrt{x}-1}-\dfrac{x+\sqrt{x}}{x-1}\right)\times\dfrac{x-1}{2x+\sqrt{x}-1}+\dfrac{\sqrt{x}}{2\sqrt{x}-1}vớix\ge0,x\ne1\)
M=\(\left(\dfrac{\sqrt{a}}{\sqrt{a}-1}-\dfrac{1}{a-\sqrt{a}}\right)\div\left(\dfrac{1}{\sqrt{a}+1}-\dfrac{2}{a-1}\right)vớia\ge0,a\ne1\)
Lm nhanh giúp mk nhé! Thank!
tìm x, biết
\(\sqrt{2x+3}=3-\sqrt{5}\)
\(\sqrt{5+\sqrt{7x}}=2+\sqrt{7}\)
\(\left(\sqrt{x}-2\right)\left(5-\sqrt{x}\right)=4-x\)
\(\dfrac{1}{2}\sqrt{x+1}-\dfrac{3}{2}\sqrt{9x-9}+24\sqrt{\dfrac{x-1}{64}}=-17\)
câu a \(\dfrac{\sqrt{m^3}+4\sqrt{mn^2}-4\sqrt{m^2n}}{\sqrt{m^2n}-2\sqrt{mn^2}}\left(m>0,n>0\right)\) câu b \(\dfrac{x\sqrt{x}-1}{x-1}\left(x>0\right)\) câu c \(\sqrt{50x^3y^5}-\dfrac{2y^2}{x^2}\sqrt{32x^7y}+\dfrac{3xy}{2}\sqrt{2xy^2}\)\(\left(x>0,y>0\right)\) câu d \(\left(x+2\right)\sqrt{\dfrac{2x-3}{x+2}}\) câu e \(\dfrac{a+b}{a}\times\sqrt{\dfrac{ab^2+ab^3}{a^2+2ab+b^2}}\left(a>0,b>-1\right)\)
Rút gọn biểu thức:
C=\(\left(\dfrac{1}{\sqrt{x}+1}-\dfrac{2\sqrt{x}-2}{x\sqrt{x}-\sqrt{x}+x-1}\right)\div\left(\dfrac{1}{\sqrt{x}-1}-\dfrac{2}{x-1}\right)vớix\ge0,x\ne1\)
D=\(\left(\sqrt{x}+\dfrac{y-\sqrt{xy}}{\sqrt{x}+\sqrt{y}}\right)\div\left(\dfrac{x}{\sqrt{xy}+y}+\dfrac{y}{\sqrt{xy}-x}-\dfrac{x+y}{\sqrt{xy}}\right)\)
Lm nhanh giúp mk nhé!
cho biểu thức Q=\(\left(\dfrac{1}{\sqrt{X}-1}-\dfrac{1}{\sqrt{X}}\right):\left(\dfrac{\sqrt{X}+1}{\sqrt{X}-2}-\dfrac{\sqrt{X}+2}{\sqrt{X-1}}\right)\)
a rút gọn Q
b tìm x để Q>0
rút gọn biểu thức
a) A=\(\dfrac{\sqrt{x}-3}{\sqrt{x-2}}-\dfrac{2\sqrt{x}-1}{\sqrt{x}-1}+\dfrac{x-2}{x-3\sqrt{x}+2}vớix\ge0,x\ne4,x\ne1\)
b)\(\left(\dfrac{x+2}{x\sqrt{x}-1}-\dfrac{\sqrt{x}}{x+\sqrt{x}+1}+\dfrac{1}{1-\sqrt{x}}\right)\div\dfrac{\sqrt{x}-1}{2}vớix>0,x\ne1\)
