Respuesta :

EVEDragon610

Answer: 45

Step-by-step explanation:

f(n) = f(1)+CD(n-1)

f(n) = 12+3(n-1)

f(n) = 12 +3n -3

f(n) = 3n+9

plug in 12 for n

f(12) = 3(12)+9

= 36 +9

=45

Answer: 45

Step-by-step explanation: 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, 42, 45