recurrence formula (1 Viewer)

[chunder]

how does the recurrence formula thing work. The cambridge book doesn't seem to make much sense. please help i'm suppose to learn this bloody concept for the holidays. what a bloody joke.

 

[spice girl]

if u get something in terms of n, you use integration by parts to reduce it to an expression of an integral in terms of n-1

e.g. I(x^n*e^x)dx = I_n

= x^n*e^x - I((nx^n-1)*e*x

= x^n*e^x - nI_(n-1)

sometimes they may ask u to put it in terms of an integral in terms of n-2, in which case you do jus that.

 

[McLake]

The idea behind it is that you may end up with an intergral in terms of itself (which simplifies) or an intergral in terms of of similar integral (ie: I = I_n-1 + 1/n*I_n-2)

 

[flyin']

Just a random comment: but for computing science (for example in c++), you will also come across recurrence!