how do you find the domain/range of y=cos(e^-x)?

Question

how do you find the domain/range of y=cos(e^-x) ??

Answer 1

domain: all real numbers (the domain of both an exponential function and cos are all real numbers)

range: [-1 , 1] -- this is the range of cos u

Answer 2

x= 0, 1, 2 --ifninity are domain

and range is

when x=0 ; e^0 =and y = cos1

when x= infinity; e^-infinity =0 and cos0 =1

these are some range values