Mathematics for IGCSE & O level - Vectors (Section 2 - No. 21)
In a parallelogram, if \(\vec{AB} = \vec{a}\) and \(\vec{AD} = \vec{b}\), which of the following is equal to \(\vec{AC}\)?
\(\vec{a} - \vec{b}\)
\(\vec{a} + \vec{b}\)
\(\vec{b} - \vec{a}\)
\(2\vec{a} + 2\vec{b}\)
คำอธิบาย
In a parallelogram, the diagonal can be found by adding the adjacent sides: AC = AB + BC. Since BC = AD, AC = a + b