Completing square HELP

Announcements
    • Thread Starter
    Online

    2
    ReputationRep:
    There's this question on completing square. 2x^2+2x. My final answer was 2(x+1/2)^2+2/4 but in my textbook the answer was 2(x+1/4)^2*1/2 .???
    Attached Images
         
    Offline

    3
    ReputationRep:
    You are correct, you are aware that 2/4 is the same as 1/2 ?
    • Thread Starter
    Online

    2
    ReputationRep:
    (Original post by B_9710)
    You are correct, you are aware that 2/4 is the same as 1/2 ?
    Yes but look inside the brackets my answer is a 1/2 but the textbooks answer was 1/4.
    Offline

    1
    ReputationRep:
    Multiply out your answer and the book's and whichever gets to the original question is correct.

    Textbooks can be wrong, remember =)
    Offline

    1
    ReputationRep:
    (Original post by bstone13)
    Multiply out your answer and the book's and whichever gets to the original question is correct.

    Textbooks can be wrong, remember =)
    Your textbook is wrong - I've worked it through and I agree with your answer.

    Assuming you meant +1/2 rather than *1/2, it give 2x^2 +x -3/8. Your answer reverts back to the original expression.
    • Thread Starter
    Online

    2
    ReputationRep:
    (Original post by bstone13)
    Your textbook is wrong - I've worked it through and I agree with your answer.

    Assuming you meant +1/2 rather than *1/2, it give 2x^2 +x -3/8. Your answer reverts back to the original expression.
    Thank you so much .I was getting worried ! I don't know how many times I redid that question and watching videos non stop to finally realise I we right. Thank you
    Offline

    1
    ReputationRep:
    (Original post by ShikaMekiFuka)
    Thank you so much .I was getting worried ! I don't know how many times I redid that question and watching videos non stop to finally realise I we right. Thank you
    You're welcome - just remember that the textbooks don't always have it right. Ask your teacher if you get stuck too
 
 
 
Write a reply… 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. Oops, you need to agree to our Ts&Cs to register
  2. Slide to join now Processing…

Updated: October 2, 2016
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.

Today on TSR
Poll
Does your body insecurities make you avoid PE or exercise?
Useful resources

Make your revision easier

Maths

Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

Equations

How to use LaTex

Writing equations the easy way

Student revising

Study habits of A* students

Top tips from students who have already aced their exams

Study Planner

Create your own Study Planner

Never miss a deadline again

Polling station sign

Thinking about a maths degree?

Chat with other maths applicants

Can you help? Study help unanswered threads

Groups associated with this forum:

View associated groups
Study resources

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

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