can x = 1 - can x+1
bphuong
x^2=2+2 can x+1
1)\(\left(DKXD:x\ge0\right)\)
\(\Leftrightarrow x+\sqrt{x\left(x+1\right)}=1\)
\(\Leftrightarrow\sqrt{x\left(x+1\right)}=1-x\)
\(\Leftrightarrow x\left(x+1\right)=1-2x+x^2\left(0\le x\le1\right)\)
\(\Leftrightarrow x^2+x=1-2x+x^2\)
\(\Leftrightarrow3x-1=0\)
\(\Leftrightarrow x=\frac{1}{3}\)
Vậy pt có nghiệm \(x=\frac{1}{3}\)
2x+2√x(x+1)+1=1
2x+2√x(x+1)=0
2√x(x+1)=−2x
4x(x+1)=4x2
x(x+1)=x2
x2+x=x2
x=0
b) tự làm sai thì thôi vì mới học lớp 7 ok
4.\(4\sqrt{x+1}=x^2-5x+14\)
ĐK \(x\ge-1\)
pT <-> \(\left(x^2-6x+9\right)+\left(x+1-4\sqrt{x+1}+4\right)=0\)
<=> \(\left(x-3\right)^2+\left(\sqrt{x+1}-2\right)^2=0\)
Do \(VT\ge0\)
=> \(\hept{\begin{cases}x=3\\\sqrt{x+1}=2\end{cases}\Rightarrow}x=3\left(tmĐK\right)\)
Vậy x=3