Hey there! Sign in to join this conversationNew here? Join for free
 You are Here: Home >< Maths

# c3 past paper maths help? watch

1. I was looking at a a past paper question that said show that:

y=5^(x+1) can be expressed as x= 1 + ( ln(y) / ln5 )

I dont undestand why they have used the natural long instead of log base 10?

Its question 4i of the ocr c3 june 2006 paper...thanks
2. (Original post by charlotte30)
I was looking at a a past paper question that said show that:

y=5^(x+1) can be expressed as x= 1 + ( ln(y) / ln5 )

I dont undestand why they have used the natural long instead of log base 10?

Its question 4i of the ocr c3 june 2006 paper...thanks
Natural log is more useful. For instance, it is a lot easier to integrate when you use natural logs (you will find this out when you do C4). It would work with log base 10 but ln is just generally more useful.
3. (Original post by charlotte30)
I was looking at a a past paper question that said show that:

y=5^(x+1) can be expressed as x= 1 + ( ln(y) / ln5 )

I dont undestand why they have used the natural long instead of log base 10?

Its question 4i of the ocr c3 june 2006 paper...thanks
This is the same thing really, any two logarithms can be converted between by multiplication with a single constant, dependent on the bases you are converting. All logarithms are variations of the same basic function.

Also I hope that's .
4. (Original post by charlotte30)
I was looking at a a past paper question that said show that:

y=5^(x+1) can be expressed as x= 1 + ( ln(y) / ln5 )

I dont undestand why they have used the natural long instead of log base 10?

Its question 4i of the ocr c3 june 2006 paper...thanks
You could use any base of logarithm to get a similar answer. All you need to do is to show that if you use the natural log then you get the relationship given

Reply
Submit reply
TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: January 12, 2015
Today on TSR

### TSR interviews Minister for Universities

Ask your questions here

### Buying condoms for the first time - help!

Discussions on TSR

• Latest
Poll
Useful resources

## Make your revision easier

### Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

### How to use LaTex

Writing equations the easy way

### Study habits of A* students

Top tips from students who have already aced their exams

Can you help? Study help unanswered threads

## Groups associated with this forum:

View associated groups
Discussions on TSR

• Latest

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Write a reply...
Reply
Hide
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.