Tangent Vector

T

r = CurveCartesian((1 + t^(2), (t * ℯ^((-t))), sin((2 * t))), t, -10, 10)
a = CurveCartesian(r'(t), t, -10, 10)
T = CurveCartesian(r'(t) / abs(r'(t)), t, -20, 20)
m = 0 (slider from -1.5 to 2, step 0.1)
A: T(m)
B: r(m)
u = Vector(B, B + A)
f = Line(B, B + A)