2. We can adapt the are longch formula to curves in 2-space that define y as a l'unction of x: Let y = f(2) define a smooth curve in 2-space. Parzanederive this carea and use the ecinition of are length to show that the kangth of the curse defined by f on an imerval Ja, b) is b 1+ [f (x)2 dx Ja