Radical equations and inequalities

2000004610

Level: 
A
Choose the correct statement about the following equation. \[ \sqrt{(x+5)^2} =x+5\]
The solution of the equation are all \( x \in [ -5; \infty) \).
The solution of the equation are all \( x \in \mathbb{R} \).
The equation has no solution in \(\mathbb{R} \).
The equation has just one root \( x=0\).

1003177803

Level: 
C
Choose the domain of the expression. \[ \frac1{\sqrt{|3x-9|-\sqrt2}} \]
\( \left(-\infty;3-\frac{\sqrt2}3\right)\cup\left(3+\frac{\sqrt2}3;\infty\right) \)
\( \left(-\infty;-3-\frac{\sqrt2}3\right)\cup\left(3+\frac{\sqrt2}3;\infty\right) \)
\( \left(-\infty;-3+\frac{\sqrt2}3\right)\cup\left(3+\frac{\sqrt2}3;\infty\right) \)
\( \left(-\infty;-3-\frac{\sqrt2}3\right)\cup\left(-3+\frac{\sqrt2}3;\infty\right) \)