binomial help (1 Viewer)

[john-doe]

can anyone show me how to do question 7 b) (ii) from 2002 maths extension 1 exam...its so hard!

here's the link..http://www.boardofstudies.nsw.edu.au/hsc_exams/hsc2002exams/pdf_doc/mathemat_ext1_02.pdf

thanks as always

 

[deswa1]

Look at the denominator- its got two consecutive integers yeah. What this suggests to me is that you'll have to integrate (twice probably) because that's what will get you those numbers on the bottom. Then you'll have to sub in some boundary conditions etc. and it should solve nicely. I don't have time now to actually try the question though- let me know if this helps. If you still can't get it and no one else does it, I'll do it sometime later tonight

 

[john-doe]

Look at the denominator- its got two consecutive integers yeah. What this suggests to me is that you'll have to integrate (twice probably) because that's what will get you those numbers on the bottom. Then you'll have to sub in some boundary conditions etc. and it should solve nicely. I don't have time now to actually try the question though- let me know if this helps. If you still can't get it and no one else does it, I'll do it sometime later tonight

ill try that...but looks doable once you showed me this way..thanks!

 

[asianese]

You need to integrate the binomial expansion of (1+x)^n twice, remembering +C for each integration. sub in x=0 or something else and it falls out well.