Question

URGENT HELP!

Answer 1

write an explicit formula for each geometric sequence
25,5,1,1/5,...

Answer 2

@Cha1234

Answer 3

@zepdrix

Answer 4

and this one
find the missing terms of geometric sequence -20,_,_,_,-1.25,...

Answer 5

@ZeHanz

Answer 6

@jim_thompson5910

Answer 7

well if r is positive, then

a(n) = a*r^(n-1)

-1.25 = -20*r^(5-1)

-1.25 = -20*r^4

-1.25/(-20) = r^4

0.0625 = r^4

r^4 = 0.0625

r = (0.0625)^(1/4)

r = 0.5


So a = -20 and r = 0.5 giving us this explicit sequence a(n) = -20*(0.5)^(n-1)

Answer 8

So if r is positive, then a(n) = -20*(0.5)^(n-1)

Answer 9

to find the missing terms, you just plug in n = 2, n = 3, and n = 4 and evaluate

Answer 10

oh ok thanks!

Answer 11

np