bài 1
a)⇔1-2x=25⇔-2x=24⇔x=-12
KL
b)⇔x²-4x+16=16⇔x²-4x=0⇔x(x-4)=0⇔\(\left[ \begin{array}{l}x=0\\x=4\end{array} \right.\)
KL
c)⇔x-5$\sqrt{x}$ +6$\sqrt{x}$ -6=0
⇔$\sqrt{x}$ ($\sqrt{x}$ -5)+`\sqrt{a}`(`\sqrt{a}`-6)=0
⇔`\sqrt{a}`(`\sqrt{a}`-5+`\sqrt{a}`-6)=0
⇔`\sqrt{a}`(2`\sqrt{a}`-11)=0
⇔\(\left[ \begin{array}{l}\sqrt{x}=0\\2\sqrt{x}-11=0\end{array} \right.\)
⇔\(\left[ \begin{array}{l}x=0\\x= \frac{11}{4} \end{array} \right.\)
KL:
Bài2
a)⇔(x-2.2.(`\sqrt{x}`+4)+(y-2.3.(`\sqrt{y}`+9)=0
⇔(`\sqrt{x}`-2)²+(`\sqrt{y}`-3)²=0
⇔\(\left[ \begin{array}{l}\sqrt{x}-2=0\\\sqrt{y}-3=0\end{array} \right.\)
⇔\(\left[ \begin{array}{l}x=4\\y=9\end{array} \right.\)
KL
b)⇔x-1-2.2.`\sqrt{x-1}`+4+y+2-2.3.`\sqrt{y+2}`+9=0
⇔(`\sqrt{x-1}`-2)²+ (`\sqrt{y+2}`-3)²=0
⇔\(\left[ \begin{array}{l}\sqrt{x-1}=2\\\sqrt{y+2}=3\end{array} \right.\)
⇔\(\left[ \begin{array}{l}x=5\\y=7\end{array} \right.\)
KL
