Write the equation in the form a = a(T)T + a(N)N at the given value of t, without finding T and N. Given r(t) = (3e^(t)cost)i + (3e^(t)sint)j + (3e^(t)sqrt(6))k, where t = 0 and a(0) = (,)T + (,)N. What is the equation in the desired form?

A) a = 3e^(t)costT + 3e^(t)sintN
B) a = 3e^(t)costT + 3e^(t)sqrt(6)N
C) a = 3e^(t)sintT + 3e^(t)sqrt(6)N
D) a = 3e^(t)costT + 3e^(t)sintN