The diagram shows a parallelogram. Read the bottom-left vertex as C C\,C and the bottom-right vertex as DDD; these two labels are interchanged in Figure 1.
[Figure 1: Diagram of a parallelogram with A at the top left, B at the top right, C at the bottom left and D at the bottom right. Diagonals AD and BC intersect at O. Vector OA is labeled 2a and vector OB is labeled 2b.]
OA⃗=2a \vec{OA} = 2\mathbf{a} OA=2a OB⃗=2b \vec{OB} = 2\mathbf{b} OB=2bFind, in terms of a\mathbf{a}a, the vector DA⃗\vec{DA}DA.
Find, in terms of a\mathbf{a}a and b\mathbf{b}b, the vector AB⃗\vec{AB}AB.
Find, in terms of a\mathbf{a}a and b\mathbf{b}b, the vector AC⃗\vec{AC}AC.
75 exam-style questions on WJEC GCSE Maths Vectors. Each one has a worked solution and a mark scheme showing where the marks go.