COMEDK2015MathematicsFunctions
If f(x)=e^ x and g(x)= e^ x , then which of the following is true?
Options
- Af g(x) g f(x)
- Bf g(x) =g f(x)
- Cf g(x) +g f(x) =0
- Df g(x) -g f(x) =1
Correct answer
B. f g(x) =g f(x)
Step-by-step solution
We have, f(x)=e^ x and g(x)= e^ x Now, f(g(x))=f ( e^ x )=e^ e^ x =e^ x and g(f(x))=g (e^ x )= e^ e^ x =e^ x e=e^ x Hence, f(g(x))=g(f(x)) .