We want to see which of the given values of x is not in the domain of f(x) = log(10 - 2x).
The correct option is (3); x = 5.
The domain is defined as the possible inputs of a given function f(x), in this particular case, we have:
f(x) = log(10 - 2x).
Remember that the logarithmic function is only defined for positive arguments, so the values of x that are NOT in the domain of f(x), are these x values such that:
10 - 2x ≤ 0
Solving it for x we have:
10 ≤ 2x
10/2 ≤ x
5 ≤ x
So any value of x equal to or larger than 5 is not in the domain of the given functions, and of the shown options, the only one that is equal or larger than 5 is x = 5, the third option.
So the correct option is the option (3).
If you want to learn more, you can read:
https://brainly.com/question/16875632
