Write the following Arithmetic sequence using an Explicit Formula: a1 = 8, an = an-1 -2
Answer:
an = 8 - 2*(n - 1)
Step-by-step explanation:
a1 ; .... ; an-1 ; an
r = an - an-1
r = (an-1 - 2) - an-1
r = an-1 - 2 - an-1
r = -2
So:
an = a1 + r*(n - 1)
an = 8 + (-2)*(n - 1)
an = 8 - 2*(n - 1)