Question

Which of the following domains provide a real value period?

Answer 1

We are given the following function:

$T=2\pi\sqrt{\frac{L}{g}}$

We are asked to determine the domain for a real-valued function.

This means we must determine which condition will ensure that the operation will yield a real number.

Since there is a radical this means that the value inside it must be always positive.

Also, inside the radical there is a rational function, therefore, the denominator must be different from zero. Therefore, the domain must be:

$g>0$

Therefore, the right option is the third option from top to bottom.