
Length of a line
Hi there, i was puzzling over this today and wonder if someone could help.
if i had a line of some equation, say
$\displaystyle y=3(x^3)+2(x^2)+x+1$
which is just some cubic, how would i calculate the length of a line between say, 0 and 5? obviously i would have to use integration by substitution, but where do i go from there?
thanks

Sorry I don't quite understand what you mean by where do i go from there, but this is the formula for calculating the length s of the path from x=a to x=b of a continuous and continuously differentiable function f(x):
$\displaystyle s = \int_a^b \sqrt{1 + f'(x)^2} dx$ .

thanks, that was helpful. i hadn't been able to find a concise approach online.