an = a1r^(n-1)
a5 = a1 r^(5-1)
-6 =a1 r^4
a2 = a1 r^(2-1)
-48 = a1 r
divide
-6 =a1 r^4
---------------- yields 1/8 = r^3 take the cube root or each side
-48 = a1 r 1/2 = r
an = a1r^(n-1)
an = a1 (1/2)^ (n-1)
-48 = a1 (1/2) ^1
divide by 1/2
-96 = a1
an = -96 (1/2)^ (n-1)
the sum
Sn = a1[(r^n - 1/(r - 1)]
S18 = -96 [( (1/2) ^17 -1/ (1/2 -1)]
=-96 [ (1/2) ^ 17 -1 /-1/2]
= 192 * [-131071/131072]
approximately -192
Answer:
16
Step-by-step explanation:
113-17= 96
96/6= 16
Answer:
Either
(approximately
) or
(approximately
.)
Step-by-step explanation:
Let
denote the first term of this geometric series, and let
denote the common ratio of this geometric series.
The first five terms of this series would be:
First equation:
.
Second equation:
.
Rewrite and simplify the first equation.
.
Therefore, the first equation becomes:
..
Similarly, rewrite and simplify the second equation:
.
Therefore, the second equation becomes:
.
Take the quotient between these two equations:
.
Simplify and solve for
:
.
.
Either
or
.
Assume that
. Substitute back to either of the two original equations to show that
.
Calculate the sum of the first five terms:
.
Similarly, assume that
. Substitute back to either of the two original equations to show that
.
Calculate the sum of the first five terms:
.
Answer:
Mr. Snowbully
Step-by-step explanation:
I think the mean hourly snowfall is named Mr. Snowbully
It's a funny name!
Well, the snow would grow at a rate of 4 cm every hour so...
4