Hey there! Sign in to join this conversationNew here? Join for free
Turn on thread page Beta
    • Thread Starter
    Offline

    2
    ReputationRep:
    Name:  image.jpg
Views: 75
Size:  521.0 KBCannot do part a) example in book is awful and wasnt shown how to do it with 3 factors. Can anyone help?
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by AndyOC)
    Name:  image.jpg
Views: 75
Size:  521.0 KBCannot do part a) example in book is awful and wasnt shown how to do it with 3 factors. Can anyone help?
    Name:  image.jpg
Views: 60
Size:  480.9 KB As far as ive got with it
    • Very Important Poster
    Offline

    21
    ReputationRep:
    Very Important Poster
    (Original post by AndyOC)
    Name:  image.jpg
Views: 75
Size:  521.0 KBCannot do part a) example in book is awful and wasnt shown how to do it with 3 factors. Can anyone help?
    If any factors aren't repeated then I believe that you just add C/third factor to how you would normally do it.
    Offline

    3
    ReputationRep:
    It's the same as you would normally do it, except with a third unknown - typically 'C'.
    Also your working is wrong, its just A B C, one for each denominator factor.
    From there you could use your own method of getting the simultaneous equations.
    • Very Important Poster
    Offline

    21
    ReputationRep:
    Very Important Poster
    (Original post by AndyOC)
    Name:  image.jpg
Views: 60
Size:  480.9 KB As far as ive got with it
    You don't need the A from the start, but the B, C and D are fine.
    Offline

    20
    ReputationRep:
    the A is superfluous
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by SeanFM)
    You don't need the A from the start, but the B, C and D are fine.
    (Original post by the bear)
    the A is superfluous
    why is it unnecessary?
    Offline

    20
    ReputationRep:
    (Original post by AndyOC)
    why is it unnecessary?
    since the order of the top of your fraction is less than the underneath you do not need any extra bits.
    Offline

    19
    ReputationRep:
    (Original post by AndyOC)
    why is it unnecessary?
    You have three linear factors and the original numerator is of order 3 or less. So you can split it into three separate fractions each with a constant numerator.
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by the bear)
    since the order of the top of your fraction is less than the underneath you do not need any extra bits.
    (Original post by Muttley79)
    You have three linear factors and the original numerator is of order 3 or less. So you can split it into three separate fractions each with a constant numerator.
    Ok but i still don't know where to go from there
    Offline

    19
    ReputationRep:
    (Original post by AndyOC)
    Ok but i still don't know where to go from there
    OK - get rid of the A - then write the right hand side over the common denominator.

    B (x + 2)(x + 1) + C (x + 3)(x + 1) + D(x + 3)(x + 2) will be the numerator.

    Can you go from here?
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by Muttley79)
    OK - get rid of the A - then write the right hand side over the common denominator.

    B (x + 2)(x + 1) + C (x + 3)(x + 1) + D(x + 3)(x + 2) will be the numerator.

    Can you go from here?
    I got that bit, and i assume you get a simultaneous equation but i don't understand how you get two separate equations when there's only a 2 on the numerator
    Offline

    19
    ReputationRep:
    (Original post by AndyOC)
    I got that bit, and i assume you get a simultaneous equation but i don't understand how you get two separate equations when there's only a 2 on the numerator
    Put x = -1 then

    2 = D(-1 + 3)(-1 + 2)

    Then repeat for other values of x to get values of B and C
    • Thread Starter
    Offline

    2
    ReputationRep:
    (Original post by Muttley79)
    Put x = -1 then

    2 = D(-1 + 3)(-1 + 2)

    Then repeat for other values of x to get values of B and C
    i see, didnt realise its that simple. thanks for the help
    Offline

    19
    ReputationRep:
    (Original post by AndyOC)
    i see, didnt realise its that simple. thanks for the help
    No problem
 
 
 
Poll
“Yanny” or “Laurel”
Help with your A-levels

All the essentials

The adventure begins mug

Student life: what to expect

What it's really like going to uni

Rosette

Essay expert

Learn to write like a pro with our ultimate essay guide.

Uni match

Uni match

Our tool will help you find the perfect course for you

Study planner

Create a study plan

Get your head around what you need to do and when with the study planner tool.

Study planner

Resources by subject

Everything from mind maps to class notes.

Hands typing

Degrees without fees

Discover more about degree-level apprenticeships.

A student doing homework

Study tips from A* students

Students who got top grades in their A-levels share their secrets

Study help links and info

Can you help? Study help unanswered threadsRules and posting guidelines

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.