Find 16th Term in Geometric Sequence

[HCL]

I keep getting B, but the answer sheet says C. I'm using ar^n= 1024((-1/2)^16)= 1/64.



Find the 16th term in the geometric sequence 1024, –512, 256, . . .

A. 1/32
B. 1/64
C. -1/32
D. -1/64

 

[Jasonrich]

I keep getting B, but the answer sheet says C. I'm using ar^n= 1024((-1/2)^16)= 1/64.



Find the 16th term in the geometric sequence 1024, –512, 256, . . .

A. 1/32
B. 1/64
C. -1/32
D. -1/64

You're using the wrong formula. The correct one is: ar^(n-1)
In this case: 1024[(-1/2)^15]

 

[HCL]

You're using the wrong formula. The correct one is: ar^(n-1)
In this case: 1024[(-1/2)^15]

that'll do it. thx

 

[Jasonrich]

that'll do it. thx

My pleasure