Answer:
An =4^(n-1)
Step-by-step explanation:
hello :
the sequence is geometric because : (-64)/(-16) = (-16)/(-4)=-4/-1= 4=r
the nth term is : An =A1 × r^(n-1)
a common ratio is : r and A1 the first term
in this exercice : r =4 A1 = 1
An =A1 × r^(n-1)
An =1 × 4^(n-1)=4^(n-1)
