Answer:
dn = -7^n-1
Explanation:
Given the sequence -1,-7,-49,-343,....
We are to find the nth term of the sequence
dn = ar^n-1
a is the first term = -1
r is the common ration = -7/-1 = -49/-7 = 7
n is the number of terms
Substitute
dn = -1(7)^n-1
dn = -7^n-1
hence the nth term of the sequence is dn = -7^n-1