If I have two different wavelength laser intensities namely: i1 , i2 passing through medium which have same linear absorption coefficient (a) for both intensities (that means i1 and i2 are variables and decreases with distance through medium (z)).
Can I describe the relation between the intensities as:
i1+i2=I.exp(-a.z)
Where I = sum of two intensities before entering the medium (i.e. I=i1(before)+i2(before)=constant)?