Vectors in two dimensions: IGCSE Mathematics questions with answers
Free Vectors in two dimensions questions for IGCSE Mathematics (0580), part of Transformations & vectors. Each question has the answer and the marking points an examiner would look for.
OABC is a parallelogram. O is the origin, OA = a and OC = c. M is the midpoint of AB.
(a)
Find AB in terms of c.
[1]
(b)
Find OM in terms of a and c.
[2]
(c)
N is the point on OB such that ON : NB = 2 : 1. Find MN in terms of a and c.
[3]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
c
c B1
1
(b)
a + ½c
OA + AM M1 a + ½c A1
2
(c)
MN = −⅓a + ⅙c
ON = ⅔(a + c) M1 MN = ON − OM M1 −⅓a + ⅙c A1
3
Question 2Structured · 9 marksA* challenge
O is the origin. The position vector of A is a and the position vector of B is b. P is the point on AB such that AP : PB = 3 : 1. M is the midpoint of OA. R is the point with position vector 32b.
Find, in terms of a and/or b, in its simplest form, the vector
(a)(i)
from A to B,
[1]
(ii)
from O to P,
[2]
(iii)
from M to P.
[2]
(b)
Show that M, P and R lie on a straight line, and find the ratio MP : PR.
[4]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)(i)
b − a
b − a B1
1
(ii)
14a + 34b
a + 34(b − a) M1 14a + 34b A1
2
(iii)
−14a + 34b
(vector OP) − ½a M1 −14a + 34b A1
2
(b)
vector MR = −½a + 32b = 2 × (vector MP); parallel with common point M, so collinear. MP : PR = 1 : 1
vector MR = −½a + 32b B1 vector MR = 2 × vector MP M1 parallel and share point M, so collinear A1 MP : PR = 1 : 1 B1
4
Question 3Structured · 4 marks
a = 11 b = 25
(a)
Find 2a − b.
[2]
(b)
Find |a + b|.
[2]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
0−3
One component correct B1 0−3B1
2
(b)
6.71
√(32 + 62) M1 6.71 oe A1
2
Question 4Structured · 7 marksA* challenge
OAB is a triangle with OA = a and OB = b. P is the point on AB such that AP : PB = 1 : 3. M is the midpoint of OA. The point R is such that OR = 3OP.
(a)
Find, in terms of a and b, in their simplest form, the vector OP.
[2]
(b)
Find MR in terms of a and b.
[2]
(c)
The line BR meets the line OA, extended, at the point X, where OX = ta. Find the value of t.
[3]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
34a + 14b
OP = a + 14(b − a) M1 34a + 14b A1
2
(b)
74a + 34b
MR = MO + OR M1 74a + 34b A1
2
(c)
t = 9
BR = −b + OR, and OX = OB + μBR M1 coefficient of b equal to zero: μ = 4 M1 t = 9 A1
3
Question 5Structured · 12 marksA* challenge
Use vectors in this question.
(a)
In triangle OAB, M is the midpoint of OA and N is the midpoint of OB. Prove that MN is parallel to AB and half its length.
[4]
(b)
PQRS is any quadrilateral. Prove that the midpoints of its four sides are the vertices of a parallelogram.
[5]
(c)
Prove that this parallelogram is a rhombus if and only if the diagonals PR and QS of the original quadrilateral are equal in length.
[3]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
MN = ½b − ½a = ½(b − a) = ½AB
OA = a, OB = b, AB = b − a B1 MN = ½b − ½a M1 = ½AB A1 so parallel and half the length A1
4
(b)
each pair of opposite sides of the midpoint quadrilateral equals ½PR or ½QS
position vectors p, q, r, s and midpoints ½(p + q) etc. M1 side joining midpoints of PQ and QR = ½(r − p) A1 side joining midpoints of RS and SP = ½(p − r) A1 opposite sides equal and parallel (same for the other pair) M1 so a parallelogram A1
5
(c)
adjacent sides are ½PR and ½QS
adjacent sides of the parallelogram are ½(r − p) and ½(s − q) M1 rhombus ⇔ these lengths are equal ⇔ PR = QS A1 both directions argued A1
3
Question 6Structured · 8 marksA* challenge
OAB is a triangle with OA = a and OB = b. P is the point on AB such that AP : PB = 1 : 3. Q is the point on OB such that OQ = 13b. The lines OP and AQ intersect at X.
(a)
Find OP in terms of a and b.
[2]
(b)
By writing OX = λOP and AX = μAQ, find the values of λ and μ.
[5]
(c)
Find the ratio OX : XP in its simplest form.
[1]
Show answers and mark scheme
Part
Answer and marking points
Marks
(a)
34a + 14b
a + 14(b − a) M1 34a + 14b A1
2
(b)
λ = 23, μ = 12
OX = a + μ(−a + 13b) M1 equate coefficients of a and of b M1 two correct equations A1 λ = 23A1 μ = 12A1
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Original Cambridge-style practice questions written for mentorriyaz.in. These are not Cambridge past paper questions, and this site is not affiliated with or endorsed by Cambridge University Press & Assessment. Updated 2026-11-04. Paper generator · mentorriyaz.in