câu 1 :tâp nhiêm cua phuong trinh(x+\(\dfrac{2}{3}\))(x-\(\dfrac{1}{2}\))=0 la câu 2:trong cac so 1;2;-2va -3thi sao nao la ngiem cua phuongg trinh x+1=2x+3 câu3:tap nhiem cua phuong trinh \(\dfrac{\left(-x+2\right)\left(2\text{x}+10\right)}{x^{2^{ }}+10\text{x}+25}\)=0la câu 4 dieu kien xac đinh cua phuong trinh \(\dfrac{x}{x-1}-\dfrac{3}{x-2}=\dfrac{5\text{x}-1}{x^{2^{ }}-3\text{x+2}}\)la câu 5:phuong trinh 2y + m=y-1nhan y = 3 la ngiem khi bang m bang câu 10 :ngiem cua phuong trinh x2+\(\dfrac{1}{x-1}=1+\dfrac{1}{1-x}\)la
Câu 1:
\(\left(x+\dfrac{2}{3}\right)\cdot\left(x-\dfrac{1}{2}\right)=0\)
=>\(\left[{}\begin{matrix}x+\dfrac{2}{3}=0\\x-\dfrac{1}{2}=0\end{matrix}\right.\)
=>\(\left[{}\begin{matrix}x=-\dfrac{2}{3}\\x=\dfrac{1}{2}\end{matrix}\right.\)
Câu 2:
x+1=2x+3
=>x-2x=3-1
=>-x=2
=>x=-2
=>-2 là nghiệm
Câu 3:
ĐKXĐ: x<>-5
\(\dfrac{\left(-x+2\right)\left(2x+10\right)}{x^2+10x+25}=0\)
=>\(\dfrac{\left(-x+2\right)\cdot2\cdot\left(x+5\right)}{\left(x+5\right)^2}=0\)
=>\(\dfrac{2\left(-x+2\right)}{\left(x+5\right)}=0\)
=>-x+2=0
=>x=2(nhận)
Câu 4:
ĐKXĐ: \(\left\{{}\begin{matrix}x-1\ne0\\x-2\ne0\end{matrix}\right.\)
=>\(\left\{{}\begin{matrix}x\ne1\\x\ne2\end{matrix}\right.\)
Câu 10: ĐKXĐ: x<>1
\(x^2+\dfrac{1}{x-1}=1+\dfrac{1}{1-x}\)
=>\(x^2-1+\dfrac{1}{x-1}+\dfrac{1}{x-1}=0\)
=>\(\left(x-1\right)\left(x+1\right)+\dfrac{2}{x-1}=0\)
=>\(\dfrac{\left(x^2-1\right)\cdot\left(x-1\right)+2}{x-1}=0\)
=>\(x^3-x^2-x+1+2=0\)
=>\(x^3-x^2-x+3=0\)
=>\(x\simeq-1,36\)
