can you tell me/?

∫  e^3x + 5e^-x  dx   =

(1/3)e^3x  +   (-5)e^-x    +  C

how can you tell me the steps?

The  best  way to see this is just  to realize the anti-derivative properties of  both functions

e^ax  has  the anti-derivative  of   (1/a) e^ax

So......letting  a  = 3  we have that

e^3x  =  (1/3)e^3x  

Similarly...lettig a  = -1   we have

5 (e ^-x)  =  5 ( e ^-1x)  =  5 ( 1/-1) (e^-1x)  =  5 (-1)e^-x  =  -5e^-x