(i)[2]
Express each of the vectors $\overrightarrow{DB}$ and $\overrightarrow{DE}$ in terms of $\mathbf{i}$, $\mathbf{j}$ and $\mathbf{k}$.
(ii)[4]
Use a scalar product to find angle $BDE$.
Mathematics 9709 · AS & A Level · Coordinate geometry
Coordinate geometry — practice question
The diagram depicts a pyramid $OABCD$ with the vertical edge $OD$ measuring 3 units. Point $E$ lies at the centre of the horizontal rectangular base $OABC$. The edges $OA$ and $AB$ are 6 units and 4 units long respectively. The unit vectors $\mathbf{i}$, $\mathbf{j}$ and $\mathbf{k}$ are parallel to $OA$, $OC$ and $OD$ respectively.