Natural Logarithms help

Watch this thread
MicroMii
Badges: 8
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#1
Report Thread starter 1 month ago
#1
Hello,

I thought I understood natural logs but when this example came in apparently you were not allowed to work it out in this way. I remember that example coming up earlier but then forgetting about it.

(attachment below):

Why cant I take the natural logarithm and simplify like this, is there a specific rule I have to follow, can someone explain when and when I can not take natural logs like this because I thought you were able to , is it only when there is a single value next to the e like e^2x and you cant take it for e^2x+1. Why is this.

Help would be appreciated, thanks
Attached files
Last edited by MicroMii; 1 month ago
0
reply
the bear
Badges: 20
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#2
Report 1 month ago
#2
cannot find an attachment
0
reply
MicroMii
Badges: 8
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#3
Report Thread starter 1 month ago
#3
(Original post by the bear)
cannot find an attachment
it should be attached at the bottom, i will attach it here
Attached files
0
reply
mqb2766
Badges: 19
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#4
Report 1 month ago
#4
(Original post by MicroMii)
it should be attached at the bottom, i will attach it here
You can divide by 10 and you can take (natural) logs. However, the right hand side doesnt simplify as you might expect as
ln(a + b)
is not
ln(a) + ln(b)
0
reply
MicroMii
Badges: 8
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#5
Report Thread starter 1 month ago
#5
(Original post by mqb2766)
You can divide by 10 and you can take (natural) logs. However, the right hand side doesnt simplify as you might expect as
ln(a + b)
is not
ln(a) + ln(b)
so would you have to do it a different way as if I was to take a ln there it would ahve to be ln (a+b)
0
reply
mqb2766
Badges: 19
Rep:
? You'll earn badges for being active around the site. Rep gems come when your posts are rated by other community members.
#6
Report 1 month ago
#6
(Original post by MicroMii)
so would you have to do it a different way as if I was to take a ln there it would ahve to be ln (a+b)
What is the original question?

Half guessing the question / your writing, Id expect that the second one is T+5 (not T+s) so express the right hand side in terms of
e^(-T/8) * (...)
then rearrange/take logs to solve for T.
Last edited by mqb2766; 1 month ago
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest

Were exams easier or harder than you expected?

Easier (22)
25.58%
As I expected (27)
31.4%
Harder (31)
36.05%
Something else (tell us in the thread) (6)
6.98%

Watched Threads

View All