Given the following geometric sequence, find the 12th term: {2, -4, 8, ...}.
1 answer:
2 times what = -4?
-2 does
-2 x 2 = -4
-4 time what = 8?
Again, -2.
-2 x -4 = 8
You could do this over and over again or make a table, or you can make a function.
f(n) = f(1) • r
f(1) in this case is 2.
f(n) = 2 • r
r is rate of change, which is -2.
f(n) = 2 • -2
To find the 12th number in the sequence, just substitute n for 12.
f(12) = 2 • -2
f(12) = 2 • -2
-2^11 = -2048
2 x -2048 = -4096
So the 12th number in the sequence will be -4096.
-2 does
-2 x 2 = -4
-4 time what = 8?
Again, -2.
-2 x -4 = 8
You could do this over and over again or make a table, or you can make a function.
f(n) = f(1) • r
f(1) in this case is 2.
f(n) = 2 • r
r is rate of change, which is -2.
f(n) = 2 • -2
To find the 12th number in the sequence, just substitute n for 12.
f(12) = 2 • -2
f(12) = 2 • -2
-2^11 = -2048
2 x -2048 = -4096
So the 12th number in the sequence will be -4096.
You might be interested in
Answer:
- 40 packages from Fred Motors
- 20 packages from Admiral Motors
- 40 packages from Chrysalis
Step-by-step explanation:
I would formulate the problem like this. Let f, a, c represent the numbers of packages bought from Fred Motors, Admiral Motors, and Chrysalis, respectively. Then the function to minimize (in thousands) is …
objective = 500f +400a +300c
The constraints on the numbers of cars purchased are …
5f +5a +10c >= 700
5f +10a +5c >= 600
10f +5a +5c >= 700
Along with the usual f >=0, a>=0, c>=0. Of course, we want all these variables to be integers.
Any number of solvers are available in the Internet for systems like this. Shown in the attachments are the input and output of one of them.
The optimal purchase appears to be …
- 40 packages from Fred Motors
- 20 packages from Admiral Motors
- 40 packages from Chrysalis
The total cost of these is $40 million.
