Integration by parts thrice! Some different approaches to a very similar examples here:
http://www.sosmath.com/CBB/viewtopic...176529#176529]
hi
have been given question : write down the definite integral that will be given of area under the curve y=x^3 cos(1/6x) between x=5/2pie and x=3pie.
unfortunately i do not even know how to begin integration of y=x^3 cos(1/6x). can some one give me some help please.
wayne
Integration by parts thrice! Some different approaches to a very similar examples here:
http://www.sosmath.com/CBB/viewtopic...176529#176529]
thanks for the link. have to admit i have no idea about integration by parts as i only started on calculus on monday,so your link is very helpful, will read carefully and post my attempts later this evening.
would like to thank you again for you time and patients i really appreciate your help.
wayne
We need to know the wording of the problem. If it refers to "the curve y = x^3 cos(1/6x)..." then no, plugging the limits into that will just give you the y values of those two points on the curve (or the difference between them). HallsofIvy is pointing out, I think, that the exercise may just be to use appropriate notation to state the quantity:
On the other hand, if it said "the integral y = x^3 cos(1/6x) gives the area under a curve", then plug away...
What is the wording?
the exact question reads
write down a definite integral that will give the value of the area under the curve y=x^3 cos(1/6x) between x=5/2 pie and 3pie.
the expression x^3 cos(1/6x) takes no negative values for 5/2pie<x<3pie.
you are not asked to evaluate the integral by hand.
part 2 of question use mathCAD to find the area described in part 1
and thats all she wrote.