Rechnung zu Aufgabe 1.2a)

c = 3*10^8; h = 6.626*10^-34; k = 1.38*10^-23; 
    T = 300;

Integrate[x^3/(Exp[x] - 1), {x, 0, ∞}]

Rechnung zu Aufgabe 1.4

c = 3*10^8; h = 6.626*10^-34; k = 1.38*10^-23; 
    T = 300;

R = (Exp[h c/(λ k T)] - 1)

λ = 10^-10; R (1 Å )

λ = 5 10^-7; R (500 nm)

λ = 5 10^-6; R (5 μm)

λ = 10^-2; R (10 mm)