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Is this in maths curriculum

Is integrating y= sin(ln x) in Edexcel A level Maths curriculum? Found this in a pre 2018 past paper. I have never come across this type of integrating in the text book.
(edited 2 months ago)
Reply 1
Original post by dent58
Is integrating y= sin(ln x) in Edexcel A level Maths curriculum? Found this in a pre 2018 past paper. I have never come across this type of integrating in the text book.

Transformation and/or by parts both of which are on the spec. It would probably be on the harder side, but its only a few lines so not v. hard.
(edited 2 months ago)
Reply 2
Original post by mqb2766
Transformation and/or by parts both of which are on the spec. It would probably be on the harder side, but its only a few lines so not v. hard.

we are not taught what to do when the function goes on by parts loop
Reply 3
Original post by dent58
we are not taught what to do when the function goes on by parts loop

1*sin(ln(x))
integrate 1 and differentate sin(ln(x)) and its not a loop.
(edited 2 months ago)
Reply 4
I ended up with xsin(lnx) - cos(lnx) dx
by parts again,
xsin(lnx) - xcos(lnx) - ∫sin(lnx) dx
Reply 5
Original post by dent58
I ended up with xsin(lnx) - cos(lnx) dx
by parts again,
xsin(lnx) - xcos(lnx) - ∫sin(lnx) dx

and if you do it again, you get the original integral +
xsin(ln(x)) - xcos(ln(x))
so its 1/2 that value.
Reply 6
Thanks for explaining! Still not sure if this is in spec though.
Reply 7
Original post by dent58
Thanks for explaining! Still not sure if this is in spec though.

On page 29
https://qualifications.pearson.com/content/dam/pdf/A%20Level/Mathematics/2017/specification-and-sample-assesment/a-level-l3-mathematics-specification-issue4.pdf
it says IBP can cover more than one application of the method but excludes reduction formulae. Using that definition it would include this question which if you did the transformation at the start it would be equivalent to integrating
e^x * sin(x)
so IBP twice to get back to the starting point and take it over and divide by 2. However, Id imagine this/they would be on the boundary of what you could be asked.
(edited 2 months ago)

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