You see that this curve goes through the point (1,0,0), when t = 0.
Then you use t=0 in T, not (1,0,0), so you have T = (((-sin(0)/sec(0)), 1, 0) = (0,1,0)
Hope that helps
Find the vectors T, N, and B at the given point.
r(t) = {cos(t), sin(t), ln(cos(t))}, (1,0,0)
I got as far as T= ((-sin(1)/sec(1)), 1, 0) but apparently my x value is wrong and that stopped me from doing the rest of the problem.