Question

integrate the following:

Answer 1

\[\int\limits_{r1}^{r2} \frac{ dr }{ r^2 }\]

Answer 2

i have never done a 1/x^2 integral :/

Answer 3

don't you know the x^n formula ?

Answer 4

1/x^2 = x^ {-2}

Answer 5

\(\int x^n dx = x^{n+1}/(n+1)+c\)

Answer 6

here n=-2

Answer 7

also, x=r :P

Answer 8

ah ok, i didnt do x^-2 thank you, but how come 1/x is lnIxI?

Answer 9

because d/dx of ln x = 1/x
so, integral of 1/x = ln x +c

Answer 10

that x^n formula is valid for all n, except n=-1

Answer 11

http://www.youtube.com/watch?v=ZGRu55zOOGU

Answer 12

ah ok :) thank you!

Answer 13

welcome ^_^