Răspuns:
Explicație pas cu pas:
(g°f)(a) = g(f(a)) = g(5) = 12
(g°f)(b) = g(f(b)) = g(1) = 12
(g°f)(e) = g(f(e)) = g(7) = -4
(g°f)(d) = g(f(d)) = g(8) = 12
(g°f)(d)g(8) = 12 · 12 = 144
f(e) = 7