Find the ninth term of the sequence sqrt 5, sqrt 10, ^2sqrt 5

sqrt 20

20 sqrt 5

16 sqrt 5

48 sqrt 5

The rule of geometric sequence is ⇒⇒⇒ a * r^ (n-1)

Where a is the first term and r is the common ratio

for the given sequence √5, √10, 2√5, ...

a = √5

r = √10 / √5 = √2

The ninth term = √5 * (√2) ^ (9-1) = √5 * (√2) ⁸ = 16 √5

the correct answer is the third option 16√5