Question

Write the first four terms in the following sequences. A(n+1)=A(n)−5 for n≥1 and A(1)=9 .

Answer 1

Explanation:

A(1) = 9

A(n+1) = A(n) - 5

n = 1 ; A(1+1) = A(1) - 5

A(2) = 9 - 5

A(2) = 4

n = 2 ; A(2+1) = A(2) - 5

A(3) = 4 - 5

A(3) = 1

n = 3 ; A(3+1) = A(3) - 5

A(4) = 1 - 5

A(4) = -4

n = 4 ; A(4+1) = A(4) - 5

A(5) = -4 - 5

A(5) = -9

First four terms are: 9 , 4 , 1 , -4 , - 9