If f(x) = 3x^2 - 5, what is the value of f(f(2))?
Just plug in 2 for the first f(x).
f(2)= 3(2^2)-5
f(2)=3(4)-5
f(2)=12-5
f(2)=7
Then plug in 7 for the second f(x)
f(7)=3(7^2)-5
f(7)=3(49)-5
f(7)=147-5
f(7)=142
f(f(2)=142
+505 
