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Partial fractions maths!

Please help. I need to find the B term so I did comparing coffcients for it. So that's 12=B but that's not right :frown:

@SeanFM @Math 123 @Maths (2x2) Life
(edited 7 years ago)

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Reply 1
IMG_4887.jpg
Reply 2


Where is the working for B? Which coefficients are you comparing to 12x?
Reply 4
Original post by Muttley79
Where is the working for B? Which coefficients are you comparing to 12x?


I can Only compare the x terms to B and that's B therefore B=12
Original post by Jane122
I can Only compare the x terms to B and that's B therefore B=12


Check the LHS again ... you have a pair of brackets there.
4a + b =12
Reply 7
Original post by Muttley79
Checj the LHS again ... you have a pair of brackets there.


But I can't use that can I? It would have an x^2 term in it
Reply 8
Original post by Hamzah249
4a + b =12


Where's the 4a from?
You're comparing the coefficients wrong. You can't simply compare A as the coefficient of the x to the power 2!

Try again but completely open all the brackets and expand the equation then compare the coefficients. Hope this helps 😊
(edited 7 years ago)
Original post by Hamzah249
....


Read the posting rules please :smile:
Original post by Jane122
Where's the 4a from?


simplify A(x+2)(x+2) and you will see that it's not just B thats the coefficient of x.

Also a tip, if comparing coefficients seems a bit confusing, you can always take any value of x to find the final constant. Take value such as x=1 or 2.
Original post by Jane122
Where's the 4a from?


There are x terms when you expand the brackets on the LHS
Reply 13
Original post by Student1256
You're comparing the coefficients wrong. You can't simply compare A as the coefficient of the x to the power 2!

Try again but completely open all the brackets and expand the equation then compare the coefficients. Hope this helps 😊


I never compared A , I already know you can't do that cause it's to the power of 2. So no , you didn't help.
Original post by Muttley79
Read the posting rules please :smile:


I guess I should have only asked him to simplify A(x+2)(x+2)
Original post by Hamzah249
simplify A(x+2)(x+2) and you will see that it's not just B thats the coefficient of x.

Also a tip, if comparing coefficients seems a bit confusing, you can always take any value of x to find the final constant. Take value such as x=1 or 2.


A better choice is usually x = 0.

Please read the guidelines before posting again in the Maths forum :smile:
Reply 16
Original post by Hamzah249
simplify A(x+2)(x+2) and you will see that it's not just B thats the coefficient of x.

Also a tip, if comparing coefficients seems a bit confusing, you can always take any value of x to find the final constant. Take value such as x=1 or 2.


I swear nobody on this thread bothered to look AT THE PIC. I've done substituting already and I need to do comparing coefficients to find the B term cause you can't do substation. Also, would it be 2A then? Not 4a?
Original post by Jane122
I never compared A , I already know you can't do that cause it's to the power of 2. So no , you didn't help.


Have you found your error yet?
Original post by Jane122
I swear nobody on this thread bothered to look AT THE PIC. I've done substituting already and I need to do comparing coefficients to find the B term cause you can't do substation. Also, would it be 2A then? Not 4a?


I don't know why you are getting all worked up on those trying to help you, we did look at the picture maybe you need to read what we said?
Reply 19
Original post by Muttley79
Have you found your error yet?


No, nobody is helping I don't understand

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