Giải PT sau: \(\sqrt{x+2\sqrt{x-1}}+\sqrt{x-2\sqrt{x-1}}=\frac{x+3}{2}\)
Giải PT sau: \(1+\frac{2}{3}\sqrt{x-x^2}=\sqrt{x}+\sqrt{1-x}\)
ĐK: \(0\le x\le1\)
Đặt \(t=\sqrt{x}+\sqrt{1-x}\) ( \(t>0\) )
\(\Leftrightarrow t^2=x+1-x+2\sqrt{x\left(1-x\right)}\)
\(\Leftrightarrow t^2-1=2\sqrt{x-x^2}\)
\(\Leftrightarrow\frac{t^2-1}{2}=\sqrt{x-x^2}\)
Ta có \(pt\Leftrightarrow1+\frac{2}{3}\cdot\frac{t^2-1}{2}=t\)
\(\Leftrightarrow1+\frac{t^2-1}{3}-t=0\)
\(\Leftrightarrow t^2-1-3t+3=0\)
\(\Leftrightarrow t^2-3t+2=0\)
\(\Leftrightarrow\left(t-1\right)\left(t-2\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}t=1\\t=2\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}\sqrt{x}+\sqrt{1-x}=1\\\sqrt{x}+\sqrt{1-x}=2\end{matrix}\right.\)
TH1: \(\sqrt{x}+\sqrt{1-x}=1\)
\(\Leftrightarrow x+1-x+2\sqrt{x\left(1-x\right)}=1\)
\(\Leftrightarrow\sqrt{x\left(1-x\right)}=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x=1\end{matrix}\right.\)( thỏa (
TH2: \(\sqrt{x}+\sqrt{1-x}=2\)
\(\Leftrightarrow x+1-x+2\sqrt{x\left(1-x\right)}=4\)
\(\Leftrightarrow\sqrt{x\left(1-x\right)}=\frac{3}{2}\)
\(\Leftrightarrow x\left(1-x\right)=\frac{9}{4}\)
\(\Leftrightarrow4x\left(1-x\right)=9\)
\(\Leftrightarrow4x^2-4x+9=0\)
\(\Leftrightarrow\left(2x+1\right)^2+8=0\)( vô lý )
Vậy \(x\in\left\{0;1\right\}\)
Giải pt: \(\frac{1}{\sqrt{x+3}+\sqrt{x+2}}+\frac{1}{\sqrt{x+2}+\sqrt{x+1}}+\frac{1}{\sqrt{x+1}+\sqrt{x}}=1\)
Giải pt \(\frac{1}{\sqrt{x-1}+\sqrt{x-2}}+\frac{1}{\sqrt{x-2}+\sqrt{x-3}}+...+\frac{1}{\sqrt{x-9}+\sqrt{x-10}}=1\)
Giải pt: \(x+\sqrt[3]{x^3-x^2}+\sqrt[3]{x^3-x}=\sqrt[3]{x^2+x+\frac{1}{3}}+\sqrt[3]{x^2+\frac{1}{3}}+\sqrt[3]{x+\frac{1}{3}}\)
giải bất pt sau:
\(\frac{\sqrt{x^{2^{ }}-x-2}}{\sqrt{x-1}}+\sqrt{x-1}< \frac{2x+1}{\sqrt{x-1}}\)
Dk 1<x<2
√x^2 -x -2<x+2
5x+6>0
X > -6/5
Bpt vô nghiệm
Giải pt sau:
\(A=\left(\frac{\sqrt{3}}{x^2+x\sqrt{3}+3}+\frac{3}{x^3-\sqrt{27}}\right)\left(\frac{x}{\sqrt{3}}+\frac{\sqrt{3}}{x}+1\right)\)
\(A=\left(\frac{\sqrt{3}}{x^2+x\sqrt{x}+3}+\frac{3}{x^3-\sqrt{27}}\right)\left(\frac{x}{\sqrt{3}}+\frac{\sqrt{3}}{x}+1\right)\)
\(\Leftrightarrow A=\left[\frac{\sqrt{3}\left(x-\sqrt{3}\right)}{\left(x-\sqrt{3}\right)\left(x^2+x\sqrt{3}+3\right)}+\frac{3}{\left(x-\sqrt{3}\right)\left(x+x\sqrt{3}+3\right)}\right]\left(\frac{x^2+3+x\sqrt{3}}{x\sqrt{3}}\right)\)
\(\Leftrightarrow A=\frac{x\sqrt{3}-3+3}{\left(x-\sqrt{3}\right)\left(x^2+x\sqrt{3}+3\right)}.\frac{x^2+x\sqrt{3}+3}{x\sqrt{3}}\)
\(\Leftrightarrow A=\frac{1}{x-\sqrt{3}}\)
Giải pt \(\frac{1}{\sqrt{x+3}+\sqrt{x+2}}+\frac{1}{\sqrt{x+2}+\sqrt{x+1}}+\frac{1}{\sqrt{x+1}+\sqrt{x}}=1\)
GIÚP MK ĐI!!!!!!!!
olm còn lỗi nên ko trình bày bth đc, bn tự viết lại nhá :))
\(\frac{1}{\sqrt{x+3}+\sqrt{x+2}}=\frac{\sqrt{x+3}-\sqrt{x+2}}{\left(\sqrt{x+3}+\sqrt{x+2}\right)\left(\sqrt{x+3}-\sqrt{x+2}\right)}\)
\(\frac{1}{\sqrt{x+2}+\sqrt{x+1}}=\frac{\sqrt{x+2}-\sqrt{x+1}}{\left(\sqrt{x+2}+\sqrt{x+1}\right)\left(\sqrt{x+2}-\sqrt{x+1}\right)}\)
\(\frac{1}{\sqrt{x+1}+\sqrt{x}}=\frac{\sqrt{x+1}-\sqrt{x}}{\left(\sqrt{x+1}+\sqrt{x}\right)\left(\sqrt{x+1}-\sqrt{x}\right)}\)
\(VT=\sqrt{x+3}-\sqrt{x+2}+\sqrt{x+2}-\sqrt{x+1}+\sqrt{x+1}-\sqrt{x}\)
\(VT=\sqrt{x+3}-\sqrt{x}=1\)
Dễ r -,-
Giải pt
\(\sqrt{2x+\frac{2013-1}{\sqrt{2-x^2}}}-\sqrt[3]{2014-\frac{2013-1}{\sqrt{2-x^2}}}=\sqrt{x+2013}-\sqrt[3]{x+1}\)
Áp dụng nội suy niu tơn để giải pt sau
\(\frac{2\left(x-\sqrt{2}\right)\left(x-\sqrt{3}\right)}{\left(1-\sqrt{2}\right)\left(1-\sqrt{3}\right)}+\frac{3\left(x-1\right)\left(x-\sqrt{3}\right)}{\left(\sqrt{2}-1\right)\left(\sqrt{2}-\sqrt{3}\right)}+\frac{4\left(x-1\right)\left(x-\sqrt{2}\right)}{\left(\sqrt{3}-1\right)\left(\sqrt{3}-\sqrt{2}\right)}=3x-1\)