The fourth term of a geometric sequence is 2 and the sixth term is 8….

The fourth term of a geometric sequence is 2 and the sixth term is 8. Find the common ratio.

Correct Answer: Option B

Explanation

(T_{n} = ar^{n – 1}) (Exponential sequence)

(T_{4} = ar^{3} = 2 …. (1))

(T_{6} = ar^{5} = 8 ……(2))

Divide (2) by (1),

(frac{ar^{5}}{ar^{3}} = frac{8}{2} )

(r^{2} = 4)

(r = pm 2)