Question

What is the rule for the following geometric sequence? 64,128,256,512...

Answer 1

Answer:

B

Step-by-step explanation:

The explicit rule for a geometric sequence is

$a_{n}$ = a₁ $(r)^{n-1}$

where a₁ is the first term and r the common ratio

Here a₁ = 64 and r = $\frac{a_{2} }{a_{1} }$ = $\frac{128}{64}$ = 2 , then

$a_{n}$ = 64 $(2)^{n-1}$ → B

Answer 2

Answer:

b).

${ \tt{a _{n} = a( {r}^{n - 1} )}} \\ { \tt{a _{n} = 64( {2}^{n - 1}) }}$