Given that:
The function to represent the growth of Neveah hair is

where, x represents the number of months since her last hair cut.
To find:
The inverse of function and time when her hair will have grown 6 inches.
Solution:
We have,

Put f(x)=y.

Interchange x and y.

Isolate y.



Put
.

So, the required inverse function is
. It represents the number of months to grow her hair x inches.
She can predict when her hair will have grown 6 inches by putting x=6 in the inverse function.
Put x=6 in the inverse function.




Therefore, growth of her hair is 6 inches in 7 months.