Question

Find the first five terms of the geometric sequence whose constant ratio is -4 and whose first term is 7.

Answer 1

7, - 28 , 112 , - 448 , 1792

Explanation:

to obtain a term in the sequence multiply the previous term by r , so

a₁ = 7

a₂ = a₁ × - 4 = 7 × - 4 = - 28

a₃ = a₂ × - 4 = - 28 × - 4 = 112

a₄ = a₃ × - 4 = 112 × - 4 = - 448

a₅ = a₄ × - 4 = - 448 × - 4 = 1792