ANSWER
B. 1
EXPLANATION
The given function is

This is a piece-wise defined function.
We want to find f(1)
We substitute x=1 into f(x)=x because, 1 belongs to the interval,
1≤x≤5
f(1)=1
The correct answer is B.
Answer:
2
Step-by-step explanation:
(,)=?
(,)=(5,2)
=5!(2!(5−2)!)
=5!2!×3!
= 10
The constants are 2, -10, and 5
the variables are x and y