Grandmother Math

SAT Exercises

If f(x) =, what is f(f(x)) ?
A) 1   B)  C)    D)    E)

solve)

f(f(x))=f(x)+

f (x) to obtain the values ​​of will ask the inverse.

If the reduction of fractions to a common denominator f(x)=

Therefore =

Answer is D)