I got B
But the ans says D
Since k can have 2 values
One is -1 and other is between 0 to 1 (which is 0.414)
Although the question says all integer values of x
I hope someone can explain
The only possible explanation I can think of is that we don’t know the value of f(k) when k is a non-integer. As in:
f(k) = x^2 + 2^k, when k is integer and
f(k) = ?, when k is not an integer
What is the source of this question?