Answer:
c
Step-by-step explanation:
Answer:
Tn = 4(-6)^n-1
Step-by-step explanation:
Write an explicit formula for an, the nth term of the sequence 4, -24, 144, ....
The sequence is a geometric sequence
Tn = ar^n-1
a is the first term
a = 4
r = -24/4 =144/-24
r = -6
Substitute
Tn = 4(-6)^n-1
Distribute.
n(n+3)
Answer : n^2+3n
