Question

Find the 8th term of the geometric sequence 5, -15, 45

Answer 1

Answer:

a₈ = - 10935

Step-by-step explanation:

the nth term of a geometric sequence is

$a_{n}$ = a₁ $(r)^{n-1}$

where a₁ is the first term and r the common ratio

here a₁ = 5 and r = $\frac{a_{2} }{a_{1} }$ = $\frac{-15}{5}$ = - 3 , then

a₈ = 5 × $(-3)^{7}$ = 5 × - 2187 = - 10935