As f(x) is linear then assume, f(x) = ax + b.
then [tex]gof = a^{2} x^{2} + a (1 + 2b)x + ( b^{2} + b - 2)[/tex]
Now compare and solve for a and b.
[tex]a^{2} = 2[/tex]
[tex]b^{2} + b - 2 = 2[/tex]
After getting a and b, just verify whether a(1 + 2b) = -5 or not.
As it's not verified so there are two possibilities.
(1) You have typed wrong function
(2) Answer is "No Such f(x) exists".
