tables of value

Question

consider the table of values for the function f(x)

x=1,2,3,4

y=f(x)=3,1,2,4

what is the value of f(f(1))?

a)1

b)2

c)3

b)4

Answer 1

Find f(1) first. when x =1 f(x)= 3, so f(1) = 3.  Now find f(f(1). since f(1) = 3,  we are looking for f(3).  When x = 3, f(x) = 2. So f(3) = 2. The answer is b.

 

whenever you are evaluating a function composition, find the inside value first then proceed to evaluate the outside function.