Recent content by jeanf

can someone show me how to do this integral: \int \frac{(1-x)}{x^2} e^{x-1} dx

yes, the question was to show that \omega is exact - sorry, i forgot to type that in my original post. i have edited it above. thanks.

let f: R^n \rightarrow R^n be differentiable, with \sum_{i=1}^n (-1)^i \frac{ \partial{f_i}}{\partial{x_i}} = 0 . show that \omega = \sum_{i=1}^n f_i dx_1 \Lambda ... \Lambda \hat{dx_i}\Lambda ... \Lamda dx_n is exact ------------------------------------- here's what i got so far...

i don't know where to start on this problem. could someone help me please? thanks. let f: A -> R be an integrable function, where A is a rectangle. If g = f at all but a finite number of points, show that g is integrable and \int_{A}f = \int_{A}g.

i have considered that, but the angles between a and b, and c and b, are different (presumably). so i end up with |a| cos(t) = |c| cos (s) ...which doesn't seem to help very much.

cross product my second question is: 2. suppose that \overrightarrow{a} X \overrightarrow{b} = \overrightarrow{c} X \overrightarrow{b} for all vectors \overrightarrow{b}. how are \overrightarrow{a} and \overrightarrow{c} related?. i wrote the vectors in terms of its components...

i need help with the following: note that the big dots represents the dot product 1. suppose that a \bullet b = c \bullet b for all vectors \overrightarrow{b} . show that \overrightarrow{a} = \overrightarrow{c} . i suppose i can't simply divide out the b, right? anyway, i tried...