You are Here: Home >< Maths

integrating 2^t Watch

1. From the Edexcel c4 2013 paper.

How do you do it? I seen people say you can do it through reverse chain rule or substitution or the ln^e(ln2)x

I learnt how do it through reverse chain rule but how do you do it the other 2 ways??
2. Couldn't it also be done by parts?

Posted from TSR Mobile
3. (Original post by Mr M)
Is that equivalent to 2^t/ln2?
4. (Original post by cera ess six)
Is that equivalent to 2^t/ln2?
Once integrated yes (plus a constant of integration).
5. (Original post by cera ess six)
Is that equivalent to 2^t/ln2?

right?

Why? a is just a number!!!
6. (Original post by Mr M)
Once integrated yes (plus a constant of integration).
Oh ok how do you integrate further? this was one of the methods which confused me completely when I saw it.
7. (Original post by Indeterminate)

right?

Why? a is just a number!!!
I don't much like the look of this!
8. (Original post by cera ess six)
Oh ok how do you integrate further? this was one of the methods which confused me completely when I saw it.
If you don't know how to tackle then you need to make sure you are confident about the basics before trying to extend your understanding further.
9. (Original post by Indeterminate)

right?

Why? a is just a number!!!
I dont understand that approach sorry
10. (Original post by cera ess six)
I dont understand that approach sorry
It is wrong so I'm not surprised you don't understand it.
11. (Original post by Indeterminate)

right?

Why? a is just a number!!!
Suspect that was a typo
12. (Original post by Mr M)
It is wrong so I'm not surprised you don't understand it.
(Original post by cera ess six)
I dont understand that approach sorry
A typo. I thought I should give one example but then decided to generalise. I forgot to change the 2 to an a
13. (Original post by Indeterminate)
A typo. I thought I should give one example but then decided to generalise. I forgot to change the 2 to an a
I assumed it probably was.
14. (Original post by Mr M)
If you don't know how to tackle then you need to make sure you are confident about the basics before trying to extend your understanding further.

Im sure integrating e^ax = 1/a e^ax just dont how it fits in X_X
15. I would write

Since

16. (Original post by cera ess six)
Im sure integrating e^ax = 1/a e^ax just dont how it fits in X_X
Try differentiating the result and see what you get.
Spoiler:
Show
Reverse chain rule
17. (Original post by joostan)
Try differentiating the result and see what you get.
Spoiler:
Show
Reverse chain rule
I know how to differentiate/integrate it reverse chain rule way.

F'(t) = 2^t ln2

Then using reverse chain rule you get 2^t/ln2

Its just the other methods of doing it I dont understand
18. (Original post by cera ess six)
Im sure integrating e^ax = 1/a e^ax just dont how it fits in X_X
Use the substitution
19. (Original post by cera ess six)
Im sure integrating e^ax = 1/a e^ax just dont how it fits in X_X
Well this is exactly the same. ln 2 is just the constant a.

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: March 25, 2013
Today on TSR

Half of the top 10 aren't even RG...

Should Disney have a gay princess?

Discussions on TSR

• Latest
• See more of what you like on The Student Room

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

• Poll
Useful resources

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

Chat with other maths applicants

Groups associated with this forum:

View associated groups
Discussions on TSR

• Latest
• See more of what you like on The Student Room

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

• 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