Question

$\frac{2-x}{x}=3$ 
$x^{2} -1=0$
[tex] \sqrt{x} +2=6
[/tex]
3x+5=x+1
aflați DVA

Answer 1

1.$\frac{2-x}{x}$=3 <=> $\frac{2}{x}$-$\frac{x}{x}$=3

$\frac{2}{x}$-1=3 . <=> $\frac{2}{x}$ =2 <=> x=1

2. $x^{2}$=1 => x=1

3. 3x-x = 5+1 => 2x= 6 => x=3

Answer 2

1.  (2-x-3x)/x=0
DVA:R-{0}
2-4x=0
4x=2
x=1/2
2.  x^2-1=0
DVA:R
x^2=1
x=1
3.   rad(x)+2=6
DVA:R-(-∞;0)
rad(x)=4
x=2
4.  3x+5=x+1
DVA:R
2x=-4
x=-2