Question

Find an explicit formula for the arithmetic sequence -5,13,31,49,...−5,13,31,49,...minus, 5, comma, 13, comma, 31, comma, 49, comma, point, point, point.

b(n)=b(n)=b, left parenthesis, n, right parenthesis, equals

Answer 1

aₙ = a₁ + (n-1) * 18 a₁ = -5

Explanation:

aₙ = a₁ + (n-1) * d a₁ = -5 d = 13 - (-5) = 18

a₂ = -5 + (2 - 1) * 18 = -5 + 18 = 13

a₃ = -5 + (3 - 1) * 18 = -5 + 36 = 31

a₄ = -5 + (4 - 1) * 18 = -5 + 54 = 49

Answer 2

a(n) = -5 + 18 (n-1)

Explanation: