Find a vector parametric equation r⃗(t) for the line through the points p=(1,0,−2) and q=(1,5,1) for each of the given conditions on the parameter t, assuming r⃗ (0)=< 1,0,−2> and r⃗ (4)=< 1,5,1> .

So the question ask to find and calculate the vector parametric equation r(t) for the line through the points P=(1,0,-2) and Q(1,5,1) for each given condition. And the possible vector parametric equation is <1,2,-2>+t/4<1,5,3>. I hope you are satisfied with my answer and feel free to ask for more 

Heya dear

df =

both have same length