giải pt: \(\left(x+1\right)\sqrt{2\left(x^2+4\right)}=x^2-x-2\)
Giải PT: \(\sqrt{\left(x^2+2x\right)^2+4\left(x+1\right)^2}-\sqrt{x^2+\left(x+1\right)^2+\left(x^2+x\right)^2}=2019\)
Chú ý:
\(\left(x^2+2x\right)^2+4\left(x+1\right)^2=\left(x^2+2x\right)^2+4\left(x^2+2x+1\right)=\left(x^2+2x\right)^2+4\left(x^2+2x\right)+4\)
\(=\left(x^2+2x+2\right)^2\)
\(x^2+\left(x+1\right)^2+\left(x^2+x\right)^2\)
\(=\left(x^2+x\right)+x^2+x^2+2x+1\)
\(=\left(x^2+x\right)^2+2x^2+2x+1\)
\(=\left(x^2+x\right)^2+2\left(x^2+x\right)+1\)
\(=\left(x^2+x+1\right)^2\)
giải pt :
a, \(\left(2x-6\right)\sqrt{x+4}-\left(x-5\right)\sqrt{2x+3}=3\left(x-1\right)\)
b, \(\left(4x+1\right)\sqrt{x+2}-\left(4x-1\right)\sqrt{x-2}=21\)
c, \(\left(4x+2\right)\sqrt{x+1}-\left(4x-2\right)\sqrt{x-1}=9\)
d, \(\left(2x-4\right)\sqrt{3x-2}+\sqrt{x+3}=5x-7+\sqrt{3x^2+7x-6}\)
giải pt :a,\(\left(2x+6\right)\sqrt{x+4}-\left(x-5\right)\sqrt{2x+3}=3\left(x-1\right)\)
b, \(\left(4x+1\right)\sqrt{x+2}-\left(4x-1\right)\sqrt{x-2}=21\)
c, \(\left(4x+2\right)\sqrt{x+1}-\left(4x-2\right)\sqrt{x-1}=9\)
d, \(\left(2x-4\right)\sqrt{3x-2}+\sqrt{x+3}=5x-7+\sqrt{3x^2+7x-6}\)
giải pt
\(\frac{2\left(x-\sqrt{2}\right)\left(x-\sqrt{3}\right)}{\left(1-\sqrt{2}\right)\left(1-\sqrt{3}\right)}+\frac{3\left(x-1\right)\left(x-\sqrt{3}\right)}{\left(\sqrt{2}-1\right)\left(\sqrt{2}-\sqrt{3}\right)}+\frac{4\left(x-1\right)\left(x-\sqrt{2}\right)}{\left(\sqrt{3}-1\right)\left(\sqrt{3}-2\right)}\)=3x-1
giải hệ pt \(\left\{{}\begin{matrix}x-3y+2\sqrt{xy}=4\left(\sqrt{x}-\sqrt{y}\right)\\\left(x+1\right)\left(y+\sqrt{xy}-x^2+x\right)=4\end{matrix}\right.\)
Giải pt:
\(4\left(x+1\right)\left(\sqrt{x+3}+\sqrt{2-x}\right)=-x^2+12x+13\)
Giải PT: \(\sqrt{x-1}+\sqrt{x+3}+2\sqrt{\left(x-1\right).\left(x^2-3x+5\right)}=4-2x\)
giải pt :
a, \(\left(x^2+2\right)^2+4\left(x+1\right)^3+\sqrt{x^2+2x+5}=\left(2x-1\right)^2+2\)
b, \(\sqrt{4x^2+x+6}=4x-2+7\sqrt{x+1}\)
c, \(\sqrt{x-2}-\sqrt{x+2}=2\sqrt{x^2-4}-2x+2\)
Giải pt, bất pt
a) \(\left(\sqrt{x+3}-\sqrt{x+1}\right)\left(x^2+\sqrt{x^2+4x+3}=2x\right)\)
b) \(\left(x^2-3x+2\right)\left(x^2-12x+32\right)\le4x^2\)
c) \(2\sqrt{3x+7}-5\sqrt[3]{x-6}=4\)
1) Giải pt: \(x=\left(2016+\sqrt{x}\right)\left(1-\sqrt{x}\right)\)
2) Giải hpt: \(\left\{{}\begin{matrix}\left(x+2\right)^2+4\left(y-1\right)^2=4xy+13\\\sqrt{\frac{x^2-xy-2y^2}{x-y}}+\sqrt{x+y}=\frac{2}{\sqrt{x^2-y^2}}\end{matrix}\right.\)
1/ ĐKXĐ: ...
\(\Leftrightarrow x=2016-2015\sqrt{x}-x\)
\(\Leftrightarrow2x+2015\sqrt{x}-2016=0\)
Đặt \(\sqrt{x}=t\ge0\)
\(\Rightarrow2t^2+2015t-2016=0\)
Nghiệm xấu kinh khủng, bạn tự giải
2. ĐKXĐ: ...
\(x^2+4x+4+4y^2-8y+4=4xy+13\)
\(\Leftrightarrow\left(x-2y\right)^2+4\left(x-2y\right)-5=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x-2y=1\\x-2y=-5< 0\left(l\right)\end{matrix}\right.\) \(\Rightarrow x=2y+1\)
Thay xuống dưới:
\(\sqrt{\frac{\left(x+y\right)\left(x-2y\right)}{x-y}}+\sqrt{x+y}=\frac{2}{\sqrt{\left(x-y\right)\left(x+y\right)}}\)
\(\Leftrightarrow\left(x+y\right)\sqrt{x-2y}+\left(x+y\right)\sqrt{x-y}=2\)
\(\Leftrightarrow3y+1+\left(3y+1\right)\sqrt{y+1}=2\)
\(\Leftrightarrow6y+\left(3y+1\right)\left(\sqrt{y+1}-1\right)=0\)
\(\Leftrightarrow6y+\frac{\left(3y+1\right)y}{\sqrt{y+1}+1}=0\)
\(\Leftrightarrow y\left(6+\frac{3y+1}{\sqrt{y+1}+1}\right)=0\Rightarrow y=0\Rightarrow x=1\)