Turn on thread page Beta
    • Thread Starter
    Offline

    15
    ReputationRep:
    x4+3x2+2

    When you integrate this, wouldn't you get: x^5/5 + x^3/3 + 2x?
    According to the mark scheme the bit in red is supposed to be 3x^3/3. Does anyone know why that is, because I have no idea. Thanks.

    Offline

    13
    ReputationRep:
    (Original post by u.sha)
    x4+3x2+2

    When you integrate this, wouldn't you get: x^5/5 + x^3/3 + 2x?
    According to the mark scheme the bit in red is supposed to be 3x^3/3. Does anyone know why that is, because I have no idea. Thanks.
    \int x^2 \ dx = \frac{x^3}{3}

    Hence,

    \int 3x^2 \ dx = \frac{3x^3}{3}
    Offline

    15
    ReputationRep:
    (Original post by u.sha)
    x4+3x2+2

    When you integrate this, wouldn't you get: x^5/5 + x^3/3 + 2x?
    According to the mark scheme the bit in red is supposed to be 3x^3/3. Does anyone know why that is, because I have no idea. Thanks.
    For integrating 3x^2
    add one to the power and divide by the new power.

    so 3x^3 /3

    (you just forgot to include the coefficient of x squared)
    • Community Assistant
    Offline

    20
    ReputationRep:
    Community Assistant
    (Original post by u.sha)
    x4+3x2+2

    When you integrate this, wouldn't you get: x^5/5 + x^3/3 + 2x?
    According to the mark scheme the bit in red is supposed to be 3x^3/3. Does anyone know why that is, because I have no idea. Thanks.
    Add one more, drop it though the trapdoor.

    And don't forget the constant of integration.
    • Thread Starter
    Offline

    15
    ReputationRep:
    (Original post by SherlockHolmes)
    \int x^2 \ dx = \frac{x^3}{3}

    Hence,

    \int 3x^2 \ dx = \frac{3x^3}{3}
    (Original post by bobwibbles)
    For integrating 3x^2
    add one to the power and divide by the new power.

    so 3x^3 /3

    (you just forgot to include the coefficient of x squared)
    (Original post by Mr M)
    Add one more, drop it though the trapdoor.

    And don't forget the constant of integration.
    ohhhhh i see where i went wrong. oh myyy :eek4:
    whoops
    thanks!!
 
 
 

University open days

  • University of Bradford
    All faculties Undergraduate
    Wed, 21 Nov '18
  • Buckinghamshire New University
    All Faculties Postgraduate
    Wed, 21 Nov '18
  • Heriot-Watt University
    All Schools Postgraduate
    Wed, 21 Nov '18
Poll
Black Friday: Yay or Nay?
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

Equations

Best calculators for A level Maths

Tips on which model to get

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

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.