Evaluate (if possible) the vector-valued function at each given value of t. (a) r(0) (b) r(/4) (c) r( - ) (d) r(/6 + t) -

Evaluate (if possible) the vector-valued function at each given value of t.

(a) r(0) 

(b) r(π/4)

(c) r(θ - π)

(d) r(π/6 + Δt) - r(π/6) 

r(t) = cos ti + 2 sin tj