Question

In an arithmetic sequence u1=7, u20=64, un=3709 find the value of common difference and find the value of n

Answer 1

Answer:

3, 1235

Step-by-step explanation:

un = 7 + (n-1)d

3709 = 7+(n-1)d

u20 = 64 = 7+19*d

19d = 57

d = 3

n = (3702/3 )+1 = 1234 + 1 = 1235