(i)[2]
Show that the vector $\overrightarrow{DE}$ is $1.6\mathbf{i} + 1.2\mathbf{j}$.
(ii)[7]
Use a scalar product to determine angle $BDO$.
Mathematics 9709 · AS & A Level · Coordinate geometry
Coordinate geometry — practice question
The diagram depicts a pyramid $OABCD$ with a horizontal rectangular base $OABC$. The edges $OA$ and $AB$ are $8$ units and $6$ units long respectively. Point $E$ lies on $OB$ in such a way that $OE = 2$ units. The vertex $D$ of the pyramid is $7$ units vertically above $E$. Unit vectors $\mathbf{i}$, $\mathbf{j}$ and $\mathbf{k}$ are parallel to $OA$, $OC$ and $OE$ respectively.