Question

Please help
Write one function for each option to describe the value of the investment f(n), in dollars, after n years. (4 points)
Number of years 1 2 3
Option 1 (amount in dollars) 1100 -1210-1331
Option 2 (amount in dollars) 1100 -1200-1300

Answer 1

Hint: Option 1 divide the yesr 2 value by the year 1 value
and the year 3 by the year 2 value
and you'll find a common ratio.

Answer 2

0.91?

Answer 3

No
year 2 / year 1
year 3 / yaer 2

Answer 4

0.90

Answer 5

1210/1100 = 0.90?

Answer 6

no it equals 1.10

Answer 7

thats more like it

Answer 8

so starting with 1100 you multiply each number by 1.1 to get the next number

Answer 9

ya I tried that but in the function I made f(x)=1100(1.10)^x it doesn't work.

Answer 10

that is incorrect because for example if you put x ( or n is best) = 1 then the YEAR 1 AMOUNT IS 1210 not 1100
so instead of n being the exponent what do you think you need?
For year n = 1 you want the function to have the value 1100(1.1)^0 which kives 1100.

Answer 11

* gives

Answer 12

Th exponent must be 'n - what'?

Answer 13

I honestly don't know

Answer 14

For n = 1, n - what has to be 0?

Answer 15

let the 'what' be x
n - x = 0
if n = 1
1 - x = 0
x = ?

Answer 16

1

Answer 17

exactly
so the exponent is (n -1)

and the formula is

f(n) = 1100(1.1)^(n-1)

Answer 18

wow it works thank you!

Answer 19

yw

Answer 20

can you help with option 2 as well?

Answer 21

For option 2 there is a COMMON DIFFERENCE of 100 and the function wiil require 1100 to be part of it and you need to ADD 100 times an expression in n.

Answer 22

No exponent here - you multuply.

Answer 23

f(n) = 1100 + 100(something)

Answer 24

1100*1.091=1200.1 this is as close as I got

Answer 25

no - just think what the 'something' might be

Answer 26

ok I've thought about it and I've come to the conclusion that its zero.

Answer 27

Its zero for year 1

Answer 28

This is similar to Otion 1

Answer 29

*Option 1.

Answer 30

is it one?

Answer 31

No- you forget that an 'n' is requred in the function?

Answer 32

an expression containig n.

Answer 33

oh wait n would be 1 for the second year ,2 for the third year and so on and so forth

Answer 34

yes

Answer 35

ok I get it now thanks

Answer 36

- not n - but an expression containing n

Answer 37

n-1?

Answer 38

the 'something in the parentheses is n-1 again.

Answer 39

yep

Answer 40

ok so like for year one n would be 1-1 and then for year 2 it would be 2-1 right?

Answer 41

gtg
hope you have learnt something - i think you have..

Answer 42

exactly

Answer 43

gtg right now

Answer 44

thanks again have a good rest of the day