Question

The range of the function f(k) = k^2+2k+1 is {25,64}. What is the function’s domain?

Answer 1

[4,7]

since 25,64 are 5 squared to 8 squared
and f(k) is (K+1) squared
then k+1 =5 and k+1=8 are the parameters
so k is 4 to 7