Find the 9th term of the geometric sequence shown here x2, 4x3, 16x4

Question

Find the 9th term of the geometric sequence shown here x², 4x³, 16x⁴

Answer 1

a_n = x²(4x)^n-1

Can you determine a₉ and answer?

Answer 2

Use the formula b_k = b₁ * r^k-1

wher r is the common ratio, say b₂/b₁ , which equals 4x

So b₉ = x² * (4x)⁸