We have the expression:

When we have rational functions, where the denominator is a function of x, we have a restriction for the domain for any value of x that makes the denominator equal to 0.
That is because if the denominator is 0, then we have a function f(x) that is a division by zero and is undefined.
If we have a value that makes f(x) to be undefined, then this value of x does not belong to the domain of f(x).
Expression:

Answer: There is no restriction for x in the expression.
Answer:

Step-by-step explanation:
Here first open the inner parentheses and use the distributive property,

Answer:
4
Step-by-step explanation:
If you mean root of x, 24-8=16
square root of 16=4
3/4 and 3/8 have to have equal denominators, so multiply 3/4 by 2/2 because it's equal to one, so it doesn't change the value of the fraction, but it makes the denominator (the number on the bottom) bigger.
3/4 x 2/2 = 6/8
Now subtract.
6/8 - 3/8 = 3/8
Don't subtract the denominators.
3/8 can't be simplified.