given that the curve is r(t) = t^2 i + t j + 2 k. indicate with an arrow the direction in which t increases.

my working:

from the equation, the curve is a parabola that cuts at (0,0,2).

i tried to find the direction that t increases, by finding grad r(t) which is (2t, 1,0) hence it should point in that direction.

however that point does not like on the curve. may i know what is wrong with my understand of this question and how it should be solved?

thanks!