Solve Unit Tangent Vector at Point P: Find T, N, B

[abralest]

Homework Statement

Find the vectors T, N, and B at the given point.
r(t) = (sin(t), cos(t), ln(cos(t))), P = (0,1,0)

Homework Equations

T(t) = r'(t) / | r'(t) |

N(t) = T'(t) / | T'(t) |

B(t) = T(t) x N(t)

The Attempt at a Solution

I am stuck on how to solve for t. I am not sure how you would calculate for the parameter t in this equation.

 

[Mark44]

You're not supposed to solve for t. You're supposed to find T (the unit tangent vector), and N and B. T is a vector and t is a scalar parameter, possibly representing time.

First thing to do is to find r'(t). Then find |r'(t)|. Use your relevant equations.