UPSC NDA Math Model Paper 4

Given: f(x)=eX and g(x)=[x] where [.] denotes smallest integer function
Here, we have to find the value of fog(9/2)
⇒ fog(9/2) = f(g(9/2))
∵ g(x) = [x] so, g(9/2) = [4.5] = 4
⇒ fog(9/2) = f(4)
∵f(x)=ex so, f(4)=e4
Hence, fog(

9

2

)=e4