Question

Suppose q(s) is an arclength-parameter curve in R2 and f(x,y) a function on R2. Show that:

d^2/ds^2 f(q(s))|s0 = d^2/ds^2 f(q(s0)+sq'(s0)) + gradf|q(s0) dot KN

where:
K = curvature at s=s0
N = unit normal at s=s0

Answer 1

dont want to get confused before my test

Answer 2

o