# Logarithms expontential growth decay help

Watch
Announcements
#1
Someone pls help me with this question I can’t figure it out because we haven’t being given either k or a
0
2 years ago
#2
(Original post by Halpme9)
Someone pls help me with this question I can’t figure it out because we haven’t being given either k or a
You're told the value of the car when it's new, i.e. when t=0.

What does equal?
0
#3
(Original post by ghostwalker)
You're told the value of the car when it's new, i.e. when t=0.

What does equal?
ah ok its 1 so 12499 = A1 meaning A = 12499 can i apply this to my equation 7000 = AK^36 meaning 7000= 12499K^36
0
2 years ago
#4
(Original post by Halpme9)
ah ok its 1 so 12499 = A1 meaning A = 12499 can i apply this to my equation 7000 = AK^36 meaning 7000= 12499K^36
Yes.
0
#5
(Original post by ghostwalker)
Yes.
ok thanks after going through with (ii) i didnt get the right answer given what have i done wrong?
7000= 12499k^36
log7000 = log12499k^36
log7000 = 36log12499k
log7000 / 36log12499 = k
0
2 years ago
#6
(Original post by Halpme9)
ok thanks after going through with (ii) i didnt get the right answer given what have i done wrong?
7000= 12499k^36
log7000 = log12499k^36
log7000 = 36log12499k
log7000 / 36log12499 = k Corrected.
0
#7
ok i did actually try this but i got lost when i my answer ended up being
k = log 7000 - log 12499 / 36log
i dont know how to divide by 36log?
0
2 years ago
#8
(Original post by Halpme9)
ok i did actually try this but i got lost when i my answer ended up being
k = log 7000 - log 12499 / 36log
i dont know how to divide by 36log?
Corrected my previous post.

So, Rearrange and taking logs: And Work it out and then take the antilog.
0
X

new posts Back
to top
Latest
My Feed

### Oops, nobody has postedin the last few hours.

Why not re-start the conversation?

see more

### See more of what you like onThe Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

### Poll

Join the discussion

#### Do you have the space and resources you need to succeed in home learning?

Yes I have everything I need (442)
56.31%
I don't have everything I need (343)
43.69%