# length of a curve help needed

• November 26th 2008, 05:56 PM
casesam
length of a curve help needed
Compute the length of the curve
r(t)=<2t,ln(t),t^2> from 1 to 2
i found r'(t), i just need help finding the square root of (4+1/t^2+4t^2)

$4t^2 + \frac{1}{t^2} + 4 =$
$\frac{4t^4 + 1 + 4t^2}{t^2} =$
$\frac{(2t^2 + 1)^2}{t^2}$