- #1
brendan
- 65
- 0
Homework Statement
Find the curvature of x = e^(t) y = e^(-t) z = t t = 0
Homework Equations
I've used the equation of
k(t) = |r'(t) x r''(t) |/ |r'(t)|^3
The Attempt at a Solution
k(t) = |r'(t) x r''(t) |/ |r'(t)|^3
= |e^t i + -e^(-t)j + 1k| x |e^t i + e^(-t)j + 0k| / |e^t i + -e^(-t)j + 1k|^3
= |-e^(-t)i + e^(t)j +2k| / |e^t i + -e^(-t)j + 1k|^3
Using t = 0
= |-e^(0)i + e^(0)j +2k| / |e^0 i + -e^(0)j + 1k|^3
= 2/1
= 2
Is this right ?
regards
Brendan