Explanation:
if I understand correctly, then f(x) has the domain of [-1, 1] and the range of [0, 1].
the domain of a function is the interval or set of the valid values of x. and the range is the interval or set of the valid values of y.
the new function we could call g(x) is
y = f(x+2) + 1
so, remember, f(x) is only defined for x values of of [-1, 1].
the argument of f(x) must never be outside that interval, or it is undefined.
the new function now uses f(x) in the form of f(x+2). that means, if we use the same x values as for the original f(x) we would land mostly in undefined areas (only x=-1 would work), because we would use f(x) with argument values from 1 to 3.
how can we regulate this back to the valid interval of -1 to 1 ?
by saying that the domain of g(x) is actually 2 less than the domain of f(x) : [-3, -1]
the "+ 1" at the end changes the range. g(x) has then a range interval that is greater by 1 than the range interval of basic f(x).
so, it is [1, 2]