(i)[5]
Show that $l$ does not meet the line through $A$ and $B$.
(ii)[6]
The point $P$, with parameter $t$, lies on $l$ and angle $PAB$ is $120^{\circ}$. Show that $3t^2 + 8t + 4 = 0$. Hence find the position vector of $P$.
Mathematics 9709 · AS & A Level · Vectors
Vectors — practice question
The position vectors of points $A$ and $B$ are $2\mathbf{i} + \mathbf{j} + 3\mathbf{k}$ and $4\mathbf{i} + \mathbf{j} + \mathbf{k}$, respectively. The line $l$ is given by $\mathbf{r} = 4\mathbf{i} + 6\mathbf{j} + u(\mathbf{i} + 2\mathbf{j} - 2\mathbf{k})$.
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