Question

Which function is an example of exponential decay?

y = 0.3(2)x
y = 4(8)x
y = 5(0.6)x
y = 1.4(3)x

Answer 1

Are any of these exponents?

Answer 2

no @ybarrap

Answer 3

Ok, anything below 1 is decay. Anything above a 0.99 is growth :)

Answer 4

0.4 is the same as 0.40 or 40% btw

Answer 5

???

Answer 6

K, um do you see those numbers in the parenthesis?

y = 0.3(2) <--x
y = 4(8)<--x
y = 5(0.6)<--x
y = 1.4(3)<--x

Those are rates at which the x is then raise to,

So suppose you're given to find f(6) in a random function like this,

f(x) = 4(0.8)^x

You carry the 6 inside the parenthesis,

f(6) = 4(0.8^6)
f(6) = 4(0.262144)

f(6) = 1.048576

So for f(x) = 4(0.8)^x the 6th number in the sequence will be 1.048576

Now see that 0.8 ? Because its below 1 it'll be a decay. If you go increasing the number of x you'll see that it goes decreasing.

Answer 7

Usually if your told to make a funtion you use this, f(x)=P(1+r)^x

You add 1 to r or rate, so 0.8 because 1.8

Answer 8

can u help me on my hw???

Answer 9

._. did you figure out which one it is?

Answer 10

ya so can u or no???

Answer 11

I can help you, but i can't give you the answers. Which one is it?

Answer 12

ya I know

Answer 13

Well? A , B ,C or D ?

Answer 14

b???

Answer 15

*shoots himself*

Answer 16

No U.U lol

ANYTHING below 1 is decay. Anything ABOVE 0.99 is growth. Now which one is it :D

Answer 17

okay gtg

Answer 18

._. tell me before you leave, a,b,c, or d D:

Answer 19

Btw, Just like its linear counterpart, exponential functions also have parameters, real world situation.

f(x)=P(1+r)^x

The P is the principal. This is the starting value, or y-intercept, when x = 0.
The r is the rate of change. Remember that if the rate is a percentage, the r will be the decimal equivalent.