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maths question help please partial fractions

hi, please could i have some help on question 2. I did partial fractions and i got A=3 C=1 B=-2 but the markscheme says something else. I then integrated it and got 3/2ln(3/2) +2ln(3/4) +1/3 but I don't know how to get it into the format they are asking for?
question and markshceme: https://files.revisely.com/documents/question-booklets/alevel/maths/ocr/Integration%20by%20Partial%20Fractions.pdf
thanks!

Reply 1

Original post
by anonymous56754
hi, please could i have some help on question 2. I did partial fractions and i got A=3 C=1 B=-2 but the markscheme says something else. I then integrated it and got 3/2ln(3/2) +2ln(3/4) +1/3 but I don't know how to get it into the format they are asking for?
question and markshceme: https://files.revisely.com/documents/question-booklets/alevel/maths/ocr/Integration%20by%20Partial%20Fractions.pdf
thanks!

Agree with the mark scheme for the coeffs so 1,0,1. If you cant find your error, upload your working.

But if youre unsure in an exam or practice, you could go from your partial fraction answer back to a single fraction, or sub a couple of values for x and see if the original fraction / your partial fraction answer agree in value.
(edited 1 year ago)

Reply 2

Original post
by mqb2766
Agree with the mark scheme for the coeffs so 1,0,1. If you cant find your error, upload your working.
But if youre unsure in an exam or practice, you could go from your partial fraction answer back to a single fraction, or sub a couple of values for x and see if the original fraction / your partial fraction answer agree in value.

no worries, i've spotted my error now! Thanks for the tip, I realised i went wrong on my notation

Reply 3

Original post
by anonymous56754
hi, please could i have some help on question 2. I did partial fractions and i got A=3 C=1 B=-2 but the markscheme says something else. I then integrated it and got 3/2ln(3/2) +2ln(3/4) +1/3 but I don't know how to get it into the format they are asking for?
question and markshceme: https://files.revisely.com/documents/question-booklets/alevel/maths/ocr/Integration%20by%20Partial%20Fractions.pdf
thanks!

i know this is an old question but when you get stuck on things like this i really suggest asking chatgpt! you have to be really precise and have a rough idea when you do but for questions like this where you just need to check bits in your workings it's really good :smile:)

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