Find the indicated nth partial sum of the arithmetic sequence.
−7, −3, 1, 5, . . ., n = 30

Step-by-step explanation:

Given the Arithmetic sequence

An arithmetic sequence has a constant difference d and is defined by

as

          ∵

    ∵  

          ∵  

Therefore, the indicated nth partial sum of the arithmetic sequence is 1530.

ANOTHER METHOD

as

n = 30

as

and

so

f(x) has value 150 at x= 0

and 0 at x= 3

so d(f(x))/dt = slope = -150/3 = -50