Calculus Problem HELP!

[DeRossi]

Show that r(t)=u(t)i+v(t)j-[u(t)+v(t)]k is a plane curve. Assume that u and v can be differentiated as often as necessary.

 

[daon2]

Do you know what torsion is?

 

[DeRossi]

Do you know what torsion is?

yes i do, but i simply don't see the connection

 

[daon2]

The torsion is zero if and only if the curve is a plane curve...