Answer
True
Work Step by Step
Given: $r(t)=t^{3}i+2t^{3}j+3t^{3}k$
All three $i,j,k$ increase linearly in relation to each other if we put $t^{3}=x$
$r(x)=xi+2xj+3xk$
Since, all the coefficients are linear in $x$ this forms a line.
Hence, the statement is true.
