1. ABCDEF is a regular hexagon with centre O. OA = a and AB = b C B Diagram drawn accurately b O D E (a) a A F Find expressions, in terms of a and b, for (i) OB Answer .................................................................. (1) (ii) AC Answer .................................................................. (1) (iii) EC Answer .................................................................. (1) (b) The positions of points P and Q are given by the vectors OP = a – b (i) OQ = a + 2b Draw and label the positions of points P and Q on the diagram. (2) (ii) Hence, or otherwise, deduce an expression for PQ . ............................……….................................................................................... ............................……….................................................................................... Answer ............................................................... (1) (Total 6 marks) The Robert Smyth School 1 2. PQRSTU is a regular hexagon and O is the centre of the hexagon. OP = p and OQ = q Express each of the following vectors in terms of p and q P U (a) PQ p T O ...................................................................................................... Q q (1) (b) SP S ...................................................................................................... R (1) (c) SQ ..................................................................................................................................... (2) (Total 4 marks) 3. The diagram shows two sets of parallel lines. Vector PQ = a and vector PS = b PR = 3PQ and PU = 2 PS U V W Not to scale S T b P (a) a Q R Write the vector PV in terms of a and b ..................................................................................................................................... Answer .................................................................. (1) (b) Write the vector RU in terms of a and b ..................................................................................................................................... Answer .................................................................. (1) (c) Find two vectors that can be written as 3a – b ..................................................................................................................................... Answer ............................ and ............................ (2) (Total 4 marks) The Robert Smyth School 2 4. In the diagram OACD, OADB and ODEB are parallelograms. OA a and OB b E D B C b O (a) a A Express, in terms of a and b, the following vectors. Give your answers in their simplest form. (i) OD ........................................................................................................................... (1) (ii) OC ........................................................................................................................... (1) (iii) AB ........................................................................................................................... Answer............................................................................... (1) (b) The point F is such that OCFE is a parallelogram. Write the vector CF in terms of a and b. ..................................................................................................................................... ..................................................................................................................................... Answer............................................................................... (2) (c) What geometrical relationship is there between the points O, D and F? Justify your answer. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (2) (Total 7 marks) The Robert Smyth School 3 5. OACB is a parallelogram and M is the mid-point of BC. OA = a and OB = b C A Not drawn accurately a M O (a) N B b Express the following vectors in terms of a and b (i) Answer .................................................................. BA (1) (ii) Answer .................................................................. AM (1) (b) AM is extended to N, where AN 2 AM . Show that BN = b ...................................................................................................................................... ...................................................................................................................................... ...................................................................................................................................... (2) (c) What does this tell you about the position of N? ...................................................................................................................................... ...................................................................................................................................... ...................................................................................................................................... (1) (Total 5 marks) 6. OP = –4a + 5b and OQ = 5a – b. P –4a + 5b O 5a – b Q R is a point on PQ such that PR : RQ = 1 : 2. The Robert Smyth School 4 (a) Express OR in terms of a and b. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... Answer .................................................... (3) (b) PS = a + 4b Express OS in terms of a and b. ..................................................................................................................................... ..................................................................................................................................... Answer .................................................... (2) (c) What two facts do OR and OS indicate about the points O, R and S? Give a reason for each of your answers. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (2) (Total 7 marks) The Robert Smyth School 5 7. In the diagram OP = 4a, PA = a, OB = 5b, BR = 3b and AQ = 2 AB 5 A a P Q 4a O 5b B R 3b Not drawn accurately (a) Find, in terms of a and b, simplifying your answers, (i) AB ........................................................................................................................... ........................................................................................................................... Answer …………………………………………… (1) (ii) PQ ........................................................................................................................... ........................................................................................................................... ........................................................................................................................... Answer …………………………………………… (2) (b) Show clearly that points P, Q and R lie on a straight line. ...................................................................................................................................... ...................................................................................................................................... ...................................................................................................................................... ...................................................................................................................................... ...................................................................................................................................... (3) (Total 6 marks) The Robert Smyth School 6 8. B Not drawn accurately Q b OAB is a triangle where M is the mid-point of OB. M P P and Q are points on AB such that AP = PQ = QB. b A a O (a) OA = a and OB = 2b Find, in terms of a and b, expressions for (i) BA ........................................................................................................................... ........................................................................................................................... Answer .......................................................... (1) (ii) MQ ........................................................................................................................... ........................................................................................................................... ........................................................................................................................... Answer .......................................................... (2) (iii) OP ........................................................................................................................... ........................................................................................................................... ........................................................................................................................... Answer .......................................................... (2) (b) What can you deduce about quadrilateral OMQP? Give a reason for your answer. ...................................................................................................................................... ...................................................................................................................................... ...................................................................................................................................... (2) (Total 7 marks) The Robert Smyth School 7 9. OPQR is a parallelogram. M is the midpoint of the diagonal OQ. OP = 2p and OR = 2r R Q 2r M O (a) 2p P Express OM in terms of p and r. ..................................................................................................................................... ..................................................................................................................................... Answer OM ....................................................... (1) (b) Use vectors to show that M is the midpoint of PR. ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... ..................................................................................................................................... (3) (Total 4 marks) The Robert Smyth School 8 The Robert Smyth School 9 1. (a) (i) a+b B1 (ii) b–a B1 (iii) a + 2b B1 or equivalent eg. b + a + b (b) (i) P in correct position Q in correct position ‘by eye’ judgement ... tolerance of 2mm in any direction (if no labels then B1, B0) B1 B1 (ii) PQ = 3b Accept PQ = PO + OQ = b – a + a + 2b = 3b B1 [6] 2. (a) – p + q oe B1 (b) 2p B1 (c) SQ = SO+ OQ or SR + RQ or SP + PQ M1 p+q A1 [4] 3. (a) a + 2b B1 oe (b) 2b –3a B1 oe a – 3a correct scores SC1 Note: and 2b 2b (c) SR UT B1 B1 (a) (i) a+b b+a B1 (ii) 2a + b 2a + b B1 –a+b B1 [4] 4. (iii) b – a (b) CF = OE M1 a + 2b (c) a + b + b oe A1 Straight line because OD = a + b B1 3 times bigger because OF = 3a + 3b B1 [7] 5. (a) (b) (i) – b + a or a – b (ii) b– 1 a 2 oe BN BM MN BM AM oe 1 1 = a+b– a 2 2 The Robert Smyth School B1 B1 M1 A1 10 (c) ON = 2 OB B1 or OBN a straight line or BN = OB or B is midpoint of ON [5] 6. (a) 1 ((4a – 5b) + (5a – b)) 3 M1 (– 4a + 5b) + their (3a – 2b) M1 dep – a + 3b A1 or 3a – 2b (b) (c) (– 4a + 5b) + (a + 4b) M1 – 3a + 9b A1 ORS is a straight line oe B1 OS is 3 times the length of OR oe B1 [7] 7. (a) (i) –5a + 5b B1 (ii) a+ M1 2 5 their(–5a + 5b) condone one error (eg, missing brackets) 2b – a (b) A1 PR = –4a + 5b + 3b M1 = – 4a + 8b or 4(2b – a) alternatively: QR = A1 3 5 (5a + 5b) +3b = 6b – 3a = 3(2b – a) PR is a multiple of PQ hence points are co-linear A1 QR is a multiple of PQ hence points are co-linear oe [6] 8. (a) (i) BA = a – 2b or equivalent B1 (ii) MQ = MB + BA = b + (a – 2b) Attempt to set up a route, must include substitution of a and b, condone one error M1 MQ = a + b or (a + b) Need not be simplified OP = OA + AB = a + (2b – a) or OP = OB + BA = 2b + (a – 2b) A1 (iii) OP = a + b M1 as above, need not be simplified for A1 The Robert Smyth School M1 A1 11 (b) OP = 2 × MQ B1 Trapezium B1 only if accompanied by a sound reason [7] 9. (a) p+r B1 (b) PM = – 2p + p + r or MR = – (p + r) 2r or PR = – 2p + 2r M1 PM = – p + r or MR = – p + r A1 PR = 2PM so M is mid-point A1 The Robert Smyth School [4] 12