FeaturesHow It WorksFor ParentsPricingContactLog inStart free — no credit card needed →

Specialist Mathematics · Unit 3 · Vectors in two and three dimensions · Algebra of vectors in three dimensions

Use multiplication by a scalar of a vector in Cartesian form.

Practise this objective

AI-marked practice questions tied to QCAA mark schemes for this exact LO. Free to start.

Start free practice

Practice questions for this objective

Full questions, answers and worked solutions unlock when you start a free practice session.

Question 1

Calculate \(2\vec{v}\) where \(\vec{v} = 3\mathbf{i} - 5\mathbf{j} + 4\mathbf{k}\).

Worked answer
🔒 Start free to see full answer
Question 2

A drone delivery service models the displacement of a package from the distribution centre to a customer as the vector \(\vec{d} = 3\mathbf{i} + 5\mathbf{j} - 2\mathbf{k}\), where distances are measured in kilometres. a) Use scalar multiplication to determine the position vector of a checkpoint located \(\frac{2}{3}\) of the way along the direct path from the distribution centre to the customer. (1 mark) b) Determine the position vector if the drone needs to travel to a location that is 4 times as far in the opposite direction from the distribution centre. (1 mark) c) Use your result from part (b) to calculate the distance from the distribution centre to this new location, correct to two decimal places. (1 mark)

Worked answer
🔒 Start free to see full answer
Question 3

A vector is given by \(\mathbf{a} = 3\mathbf{i} - 2\mathbf{j} + 5\mathbf{k}\). Determine the vector \(-4\mathbf{a}\) in Cartesian form.

Worked answer
🔒 Start free to see full answer
Question 4

Use scalar multiplication to determine the vector \(3\vec{OB}\) where \(\vec{OB}\) is shown in the diagram below.

Worked answer
🔒 Start free to see full answer
Unlock all 4 answers — free

More in Algebra of vectors in three dimensions

← Previous
Use a vector representing a section of a line segment, including the midpoint of a line segment.
Next →
Use scalar and vector projections of vectors. scalar projection of 𝒂 on 𝒃: |𝒂| cos(𝜃) = 𝒂 ⋅ 𝒃̂ vector projection of 𝒂 on 𝒃: |𝒂| cos(𝜃) 𝒃̂ = (𝒂 ⋅ 𝒃̂)𝒃̂ = (𝒂⋅𝒃 𝒃⋅𝒃) 𝒃
All LOs in Algebra of vectors in three dimensionsBack to full Specialist Mathematics syllabus