Radical equations and inequalities

9000020006

Level: 
A
Identify a true statement referring to the solution of the following equation. \[ \sqrt{3x - 8} = x - 6 \]
The equation has a unique solution and this solution is an odd number.
The equation has two solutions, the sum of these solutions is divisible by \(5\).
The equation has a unique solution and this solution is an even number.
The equation does not have a solution in \(\mathbb{R}\).

9000020007

Level: 
A
Identify a true statement referring to the solution of the following equation. \[ \sqrt{x^{2 } - 4} = x + 1 \]
The equation does not have a solution in \(\mathbb{R}\).
The equation has a unique negative solution.
The equation has a unique positive solution.
The equation has two solutions.

9000020008

Level: 
A
Identify a true statement referring to the solution of the following equation. \[ 6x - 13\sqrt{x} + 6 = 0 \] Hint: Use the substitution \(y = \sqrt{x}\).
The solutions \(x_{1}\) and \(x_{2}\) satisfy \(x_{1} = \frac{1} {x_{2}} \).
The equation has a unique solution \(x_{1}\). This solution satisfies \(x_{1} < 1\).
The equation has a unique solution \(x_{1}\). This solution satisfies \(x_{1} > 1\).
The equation does not have a solution in \(\mathbb{R}\).

9000022305

Level: 
A
Find the domain of the following expression. \[ \sqrt{-x^{2 } + 16x - 63} \]
\(\left [ 7;9\right ] \)
\(\left (-\infty ;7\right )\cup \left (9;\infty \right )\)
\(\left (-\infty ;-7\right ] \cup \left [ 9;\infty \right )\)
\(\left (7;9\right )\)
\(\left [ -7;9\right ] \)