Answer:
1
Step-by-step explanation:
so, the function is defined as coordinate pairs.
the first coordinate is x (and is the input variable), the second is y (the function result).
a function result is sometimes also called image, as some input information is converted into something else that can then be used, seen, stored, ...
so, the function result = y = 2 and is the result of x²+1.
2 = x² + 1
1 = x²
x = 1
so, 1 is the "pre-image" of 2 for this function. as 2 is the image of 1 under this function.
