Find the domain of \(g(x) = \frac{4x^{2} - 1}{\sqrt{9x^{2} + 1}}\)

To find the domain of the given function, we need to identify any values of x that would make the denominator of the fraction equal to zero or negative, as these values would result in an undefined function. Additionally, we need to consider any other restrictions on x that may arise from the function's algebraic properties. In this case, the denominator of the function is the square root of \(9x^{2} + 1\). Since the square root of a negative number is not defined in the real number system, we know that the expression inside the square root must be non-negative. This means that: \(9x^{2} + 1 \geq 0\) Solving this inequality, we get: \(9x^{2} \geq -1\) Dividing both sides by 9, we get: \(x^{2} \geq -\frac{1}{9}\) Since the square of any real number is non-negative, we know that this inequality is satisfied for all real values of x. Therefore, there are no values of x that would make the denominator of the function equal to zero or negative, and the domain of the function is all real numbers. In other words, the correct answer is: \(x: x \in R\)