Results are out! Find what you need...fast. Get quick advice or join the chat
x

Unlock these great extras with your FREE membership

  • One-on-one advice about results day and Clearing
  • Free access to our personal statement wizard
  • Customise TSR to suit how you want to use it

The function lnx

Announcements Posted on
Find your uni forum to get talking to other applicants, existing students and your future course-mates 27-07-2015
Win top prizes in our mega results day giveaway... 24-07-2015
  1. Offline

    ReputationRep:
    Is this right?

    e^2x+1 = 2
    2x +1 = ln 2
    x = 0.5 ln( 2- 1)

    I though for the last step:

    x = 0.5 (ln(2) -1)

    with the one outside the ln brakets?
  2. Offline

    ReputationRep:
    You are correct. The last step is x = 0.5 (ln(2)-1)
  3. Offline

    ReputationRep:
    (Original post by CharlieBoardman)
    You are correct. The last step is x = 0.5 (ln(2)-1)
    Thats what is thought but the mark sheme says this

    0.5 ln( 2- 1)
  4. Offline

    (Original post by nazgul60)
    Thats what is thought but the mark sheme says this

    0.5 ln( 2- 1)
    That's wrong.
  5. Offline

    ReputationRep:
    (Original post by nazgul60)
    Thats what is thought but the mark sheme says this

    0.5 ln( 2- 1)
    It is wrong because that gives 0.5ln(1) = 0 and this can be easily disproved by substituting x=0 into the initial equation.
  6. Offline

    ReputationRep:
    (Original post by Micky76)
    It is wrong because that gives 0.5ln(1) = 0 and this can be easily disproved by substituting x=0 into the initial equation.
    Thats what i thought but just needed to be confident. Thanks!
  7. Offline

    ReputationRep:
    Am I just being stupid or isn't x=0 the answer?
  8. Offline

    ReputationRep:
    e^{2x+1}=2

    or

    e^{2x}+1=2
  9. Offline

    ReputationRep:
    (Original post by BabyMaths)
    e^{2x+1}=2

    or

    e^{2x}+1=2
    Is it not multiplied by e instead of the +1?
  10. Offline

    ReputationRep:
    (Original post by BabyMaths)
    e^{2x+1}=2


    that one
  11. Offline

    ReputationRep:
    (Original post by BabyMaths)
    e^{2x+1}=2

    or

    e^{2x}+1=2
    Sorry, my bad in the interpretation of your post.
  12. Offline

    ReputationRep:
    (Original post by nazgul60)
    that one
    In that case x=\frac{1}{2}(-1+\ln 2) as you thought.
  13. Offline

    ReputationRep:
    (Original post by nazgul60)
    Thats what is thought but the mark sheme says this

    0.5 ln( 2- 1)
    Sometimes mark schemes have mistakes in them. Don't worry - you are correct!
  14. Offline

    ReputationRep:
    (Original post by nazgul60)
    that one
    Then you are right/mark scheme is wrong.

    probably just a typing error by a clerk who doesn't know to be careful with these things.

Reply

Submit reply

Register

Thanks for posting! You just need to create an account in order to submit the post
  1. this can't be left blank
    that username has been taken, please choose another Forgotten your password?
  2. this can't be left blank
    this email is already registered. Forgotten your password?
  3. this can't be left blank

    6 characters or longer with both numbers and letters is safer

  4. this can't be left empty
    your full birthday is required
  1. By joining you agree to our Ts and Cs, privacy policy and site rules

  2. Slide to join now Processing…

Updated: June 12, 2012
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.

New on TSR

Results are coming...

No sweat. Here's all you need to make sure you're ready

Study resources
x

Think you'll be in clearing or adjustment?

Hear direct from unis that want to talk to you

Get email alerts for university course places that match your subjects and grades. Just let us know what you're studying.

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