GRADE 12 EXAMINATION NOVEMBER 2008 ADVANCED PROGRAMME MATHEMATICS MARKING GUIDELINES Time: 3 hours 300 marks These marking guidelines are prepared for use by examiners and sub-examiners, all of whom are required to attend a standardisation meeting to ensure that the guidelines are consistently interpreted and applied in the marking of candidates' scripts. The IEB will not enter into any discussions or correspondence about any marking guidelines. It is acknowledged that there may be different views about some matters of emphasis or detail in the guidelines. It is also recognised that, without the benefit of attendance at a standardisation meeting, there may be different interpretations of the application of the marking guidelines. IEB Copyright © 2008 PLEASE TURN OVER GRADE 12 EXAMINATION: ADVANCED PROGRAMME MATHEMATICS – MARKING GUIDELINES MODULE 1 Page 2 of 18 CALCULUS AND ALGEBRA QUESTION 1 1.1 (a) (b) or (x – 1) (x 2 + x + 1) 9 x = 19 x2 + x + 1 = 0 9 – 1 ± 1– 4 2 – 1 + 3i ∴ x= or 2 (1) (5) ∴ x= 1.2 – 1 – 3i 2 999 (x − 1 − 2 )(x − 1 + 2 )99 = x 2 − x + 2 x − x + 1 − 2 − 2 x + 2 − 2 999 or ( x − 1) 2 − ( 2 ) 2 = x 2 − 2 x − 1 is a factor. 99 By inspection: x 4 − 2 x 3 + 4 x 2 − 10 x − 5 = (x 2 − 2 x − 1)(x 2 + 5) = ( x 2 – 2 x – 1 )( x – 5 i )( x + 5i ) 999 (10) 16 marks QUESTION 2 2.1 (a) (b) (c) log 2 x − log( x − 20 ) = 1 9 2x ∴ log =1 x − 20 99 2x ∴ = 10 x − 20 ∴ 2 x = 10 x − 200 ∴ 8 x = 200 ∴ x = 25 9 (4) e x = 5e x − 5 9 ∴ 4e x = 5 9 ∴ e x = 1,25 9 ∴ x = ln 1,25 = 0,223... 9 (4) Let k = x 9 (k − 6)(k + 2) = 0 99 x =6 ∴ x = ±6 IEB Copyright © 2008 99 x ≠ −2 9 (6) GRADE 12 EXAMINATION: ADVANCED PROGRAMME MATHEMATICS – MARKING GUIDELINES 2.2 Page 3 of 18 ⎛ L ⎞ 107 = 10 log⎜ −16 ⎟ 99 ⎝ 10 ⎠ 10,7 = log L − log 10 −16 99 ∴ − 5,3 = log L 99 ∴ L = 10 −5,3 = 5,01 × 10-6 (6) 20 marks QUESTION 3 Prove: x k +1 − y k +1 9 9is divisible by x − y . x k .x − y k . y 99 = p ( x − y ) + y k .x − y k . y from Step 299 = px( x − y ) + xy k . − y k . y 99 = px( x − y ) + y k ( x − y ) = (x − y )( px + y k ) 99 ( ( ) ) So we have shown that provided that x k − y k is divisible by x − y then so is x k +1 − y k +1 . But since the statement is true for n = 1, then by the argument above it is true for n = 2, and hence n = 3 and so on for all natural values of n. 99 12 marks IEB Copyright © 2008 PLEASE TURN OVER GRADE 12 EXAMINATION: ADVANCED PROGRAMME MATHEMATICS – MARKING GUIDELINES QUESTION 4 4.1 f ( x) = (a) ( ) ex ex −1 3e x 1 1 ∴ f ( x) = e x − 99 3 3 (b) y (2) 99 9 O x − 13 9 4.2 Page 4 of 18 (4) At Q, log(2 x + 3) = 1 9 ∴ 2 x + 3 = 10 99 7 ∴x = 2 At P, log(2 x + 3) = −1 ∴ 2x + 3 = 1 10 ∴ x = − 29 20 999 (6) 12 marks QUESTION 5 5.1 5.2 3 − a(1) 2 = −4(1) + 5 999 ∴ a = 2 99 ⎧ 3 − 2 x 2 if f ( x) = ⎨ ⎩− 4 x + 5 if x ≥1 x <1 lim f ' ( x) = −4 999 h→0 − (5) lim f ' ( x) = −4(1) = −4 999 h →0 + Therefore differentiable at x = 1. 9 99method (9) 14 marks IEB Copyright © 2008 Page 5 of 18 GRADE 12 EXAMINATION: ADVANCED PROGRAMME MATHEMATICS – MARKING GUIDELINES QUESTION 6 2 x 2 − 5x + 2 2x 2 − x − 1 (2 x − 1)(x − 2) 9 = (2 x + 1)(x − 1) 2 x 2 − 5x + 2 = 0 (2 x − 1)(x − 2) = 0 9 x = 1 or 2 9 2 g ( x) = 6.1 x= 6.2 1 2 or x = 2 9 x →∞ Horizontal: 2 − 5x + x22 2 − 1x − x12 x = 1 99 999 = 1 y = 19 (7) 2 x 2 − x − 1) ( 4 x − 5 ) − ( 2 x 2 − 5 x + 2 ) ( 4 x − 1) ( 999999 g '( x) = 2 2 2 x − x − 1 ( ) = 6.4 (2) 2x2 – x – 1 (2 x + 1) (x − 1) 9 x = − 12 and Vertical: lim 6.3 or 8 x 2 − 12 x + 7 (2 x 2 − x − 1) 2 99 (8) Δ = 144 − 4(8)(7) = −80 9 8 x 2 − 12 x + 7 ≠ 0 9 Therefore no local max or min turning point. 9 (3) y 6.5 9 9 9 –2 9 x= − 12 1 2 29 9 x=1 9 y=1 x (7) 27 marks IEB Copyright © 2008 PLEASE TURN OVER GRADE 12 EXAMINATION: ADVANCED PROGRAMME MATHEMATICS – MARKING GUIDELINES Page 6 of 18 QUESTION 7 7.1 7.2 ( ) ⎛ 1 − 12 ⎞ ⎜1 + x ⎟ 999999 ⎜ 2 ⎟ ⎝ ⎠ cos(a − x ). cos x + sin x(− sin (a − x )(− 1)) 9999 = cos(a − x ) cos x + sin( a − x) sin x 9 = cos(a − x − x) 9 = cos(a − 2 x) 9 1 f ' ( x) = x + x 2 − 1 2 (6) (7) 13 marks QUESTION 8 dy 8.1 = 2t 9 dt dy 1 = 2t × 99 dx 3 8.2 dx = 39 dt = 2t 3 (4) 1 2 = 2t × 99 3 t = 39 x = 3(3) + 1 = 10 9 y = 32 = 9 (10;9) 9 (5) 9 marks QUESTION 9 9.1 3 solutions99 (2) 9.2 x = 0,59 (1) 9.3 − x + 1 = x 3 − 5x 2 + 6 x ∴ 0 = x 3 − 5x 2 + 7 x − 1 x r +1 999 x 3 − 5x 2 + 7 x − 1 9999 = xr − 3 x 2 − 10 x + 7 x1 = 0.59 x2 = 0 x3 = … ……… x = 0,160713 (6 dp) 99 (10) 13 marks IEB Copyright © 2008 GRADE 12 EXAMINATION: ADVANCED PROGRAMME MATHEMATICS – MARKING GUIDELINES Page 7 of 18 QUESTION 10 10.1 y ' = 3ax 2 + 2bx + c 999 y ' ' = 6ax + 2b 0 = 6a (2) + 2b b = −6a 10.2 99 (5) − 3 = 3a (0) + 2b(0) + c 999 ∴ c = −3 Passes through (0;0) ∴ d = 0 9 Passes through (2; -22) ∴ −22 = 8a + 4b − 6 99 ∴ b = −2a − 4 ∴ −6a = −2a − 4 ∴a =1 9 ∴ b = −6 9 y = x 3 − 6 x 2 − 3x 9 (9) 14 marks QUESTION 11 11.1 11.2 π⎞ ⎛ P = 3 × ⎜ 2 × ⎟ 99 3⎠ ⎝ = 6,28 cm 9 (3) 9999999 1 π π π⎤ 1 ⎡1 A = Δ ABC + 3 segments = × 2 × 2 × sin + 3⎢ × 2 2 × − × 2 × 2 × sin ⎥ 3 2 3⎦ 2 3 ⎣2 2 = 2,82 cm 9 or A = 1 Sector + 2 segments = 1 × 2 2 × π + 2 ⎡ 1 × 2 2 × π − 1 × 2 × 2 × sin π ⎤ ⎢⎣ 2 2 3 3 2 3 ⎥⎦ or A = 3 sectors – 2 triangles = 3 ⎡ 1 × 2 2 × π ⎤ − 2 ⎡ 1 × 2 × 2 × sin π ⎤ ⎢⎣ 2 ⎢⎣ 2 3 ⎥⎦ 3 ⎥⎦ (8) 11 marks IEB Copyright © 2008 PLEASE TURN OVER Page 8 of 18 GRADE 12 EXAMINATION: ADVANCED PROGRAMME MATHEMATICS – MARKING GUIDELINES QUESTION 12 3 ( ) 2 ∫ x x −1 12.1 − 1 2 dx 9 or u = x2 − 1 Let 2 3 = ( ) 1 − 1 2 2 dx 99 2 x x − 1 2 ∫2 du = 2 x dx 3 1 = ⎡⎢(x 2 − 1)2 ⎤⎥ 9999 ⎣ ⎦2 dx = du 2x 3 = ∫ 8 − 3 = 1,10 units999 2 8 x x −1 2 dx = ∫ 3 1 du 2 u 8 ⎡ 1⎤ = ⎢u 2 ⎥ ⎣ ⎦3 = 8− 3 = 1,10 12.2 5−3 = 0,4 99 5 (a) x1 = 3, 4 h1 = ln 3, 4 Area1 = 0, 4895 x2 = 3,8 h2 = ln 3,8 Area2 = 0,5340 x3 = 4, 2 h3 = ln 4, 2 Area3 = 0,5740 9999999 x4 = 4, 6 h4 = ln 4, 6 Area4 = 0, 6104 x5 = 5 h5 = ln 5 Area5 = 0, 6438 2 TOTAL = 2,852 units 9 (b) (10) (10) [x ln x − x]53 9 = 5.ln 5 − 5 − 3ln 3 + 3 9999 = 2, 751 units 2 9 (6) 26 marks QUESTION 13 1 1 1 V = ∫ π (4 − 4 x )dx − ∫ π (1 − x )dx 9999 2 −1 2 −1 1 V = ∫ π (3 3x 2 ) dx 1 1 ⎡ ⎡ x3 ⎤ 4x3 ⎤ = π ⎢4 x − ⎥ − π ⎢ x − ⎥ 9999 3 ⎦ −1 3 ⎦ −1 ⎣ ⎣ = π [3x x 3 ] 1 4⎤ 1⎤ ⎡ 4 ⎡ 1 = π ⎢ 4 − + 4 − ⎥ − π ⎢1 − + 1 − ⎥ 9999 3⎦ 3⎦ ⎣ 3 ⎣ 3 = π [(3 1) ( 3 + 1)] = 4π units 3 9 1 = 4π units 3 13 marks IEB Copyright © 2008 GRADE 12 EXAMINATION: ADVANCED PROGRAMME MATHEMATICS – MARKING GUIDELINES MODULE 2 Page 9 of 18 STATISTICS QUESTION 1 1.1 1.2 H 0 = 3118 H1 ≠ 3118 (4) 3333 Testing for change therefore involves two rejection regions. 5% level of significance means each region is 2,5%. 3 The critical value that corresponds is 1,96. 3 Z= x−μ σ 3 n Z= 3345 − 3118 850,5 40 0.025 333 0.025 1,96 Z = 1,688 This value of Z falls within the acceptance region, therefore not enough evidence to reject H 0 . Accept H 0 3 1.3 1,96 = (7) x − 3118 33 850,5 40 x = 3381,6 g 33 (4) 15 marks IEB Copyright © 2008 PLEASE TURN OVER GRADE 12 EXAMINATION: ADVANCED PROGRAMME MATHEMATICS – MARKING GUIDELINES Page 10 of 18 QUESTION 2 2.1 As x increases y decreases. 33 2.2 (a) (b) 2.3 b= r = −0,98 3333 very strong correlation 3 n∑ xy − ∑ x ∑ y n ∑ x 2 − (∑ x ) 2 (2) (4) (1) 33 n = 12 3 12(3291,88) − 511(78,52) 12(289490) − (511) 2 333 b = −0,0072 y − y = b( x − x ) b= Now for a: y − 6,54 = −0,0072( x − 42,58) 3333 y = −0,0072 x + 6,85 2.4 (a) (b) y = 6,85 − 0,0072(95) 333 y = 6,17 unreliable, outside of range, extrapolation33 (10) (3) (2) 22 marks IEB Copyright © 2008 GRADE 12 EXAMINATION: ADVANCED PROGRAMME MATHEMATICS – MARKING GUIDELINES Page 11 of 18 QUESTION 3 3.1 Proportion not in favour = Proportion in favour = 202 3 700 498 700 90% confidence interval z= 1,6453 p (1 − p ) 3 n 202 498 × 202 700 700 333 ± 1,645 700 700 [0,260399; 0,316742] 3333 p ± 1,645 3.2 (a) 105,89 + 110,11 = 108 33 2 (b) 105,89 = 108 − 1,96 σ = 28,48 33 3 3.3 3 σ 700 (10) (2) 3 ⎛10 ⎞ ⎛10 ⎞ 1 − ⎜⎜ ⎟⎟(0,55)1 (0,45) 9 − ⎜⎜ ⎟⎟(0,45)10 33 ⎝1 ⎠ ⎝0 ⎠ = 0,99533 (6) 3333 33 (9) 27 marks IEB Copyright © 2008 PLEASE TURN OVER GRADE 12 EXAMINATION: ADVANCED PROGRAMME MATHEMATICS – MARKING GUIDELINES Page 12 of 18 QUESTION 4 4.1 4.2 4.3 8! – 7! x 2! 99 = 30240 9 (3) 0,1 1 9 = 0,5 5 0,4 4 (b) = 9 0,5 5 (c) P (A) . P (B) = 0,4 x 0,5 = 0,2 9 and P (A∩B) = 0,1 9 ∴ not equal ∴ not independent 9 ⎧ ⎛ 4 ⎞⎛ 8 ⎞ ⎟⎟ ⎪ ⎜⎜ ⎟⎟⎜⎜ ⎪⎪ ⎝ x ⎠⎝ 3 − x ⎠ (a) P ( X = x) = ⎨ for ⎛12 ⎞ ⎜⎜ ⎟⎟ ⎪ ⎝3 ⎠ ⎪ ⎪⎩0 elsewhere ⎛ 4 ⎞⎛ 8 ⎞ ⎜⎜ ⎟⎟⎜⎜ ⎟⎟ ⎝ 2 ⎠⎝1 ⎠ = 12 33333 (b) 55 ⎛12 ⎞ ⎜⎜ ⎟⎟ ⎝3 ⎠ (a) (1) (1) (3) x = 0,1,2,3 formula 33333 (6) 3 (5) 6 4.4 (a) ∫ (0,2 − 0,02 x)dx 33 2 x − x2 5 100 6 99 2 = 6 − 36 − ( 2 − 4 ) 33 5 100 5 100 = 0,48 33 Probability delay would be between 2 and 6 hours is 0,48 (b) x − x2 5 100 (8) m 33 = 0,533 0 m m2 − = 0,5 3 5 100 20m 2 − 400m + 1000 = 0 3333 m = 2,93 or m = 17,07( N / A) (9) 36 marks IEB Copyright © 2008 GRADE 12 EXAMINATION: ADVANCED PROGRAMME MATHEMATICS – MARKING GUIDELINES MODULE 3 Page 13 of 18 FINANCE AND MODELLING QUESTION 1 1.1 9 9 5 2 7 P(1 − 0,2) (1 − 0,4) = P(1 − i ) 9 0,1179648 = (1 − i ) 0,7368... = 1 − i i = 26,31% 9 7 9 9 (6) 1.2 A B C D Paying more than the required amount in order to pay back more quickly. 99 Cash flow problem - Paying only sufficient to cover interest. 99 Interest rates rise. Paying less than the required amount. 99 Gets promotion, bigger salary. Able to pay more per month and finish the loan in the right time. 99 (8) 14 marks QUESTION 2 2.1 9 99 −n ⎡ 0 ,095 ⎞ ⎤ ⎛ 99 3 9 ⎢1 − ⎜1 + 12 ⎟ ⎥ ⎛ 0,095 ⎞ ⎝ ⎠ ⎥ 6000000⎜1 + ⎟ = 55000 ⎢ ⎥ ⎢ 0 , 095 12 ⎠ ⎝ ⎥ ⎢ 12 ⎥⎦ ⎢⎣ n = 273,5 months 999 So 276 months in total = 23 years 9 2.2 (10) Amount remaining = 9 ⎡ ⎛ 0,095 ⎞ 21 ⎤ 99 24 99 ⎢ ⎜1 + ⎟ − 1⎥ 12 ⎠ ⎛ 0,095 ⎞ ⎝ ⎢ ⎥ 99 6000000⎜1 + ⎟ − 55000 ⎢ ⎥ 0 , 095 12 ⎠ ⎝ ⎢ ⎥ 12 ⎣⎢ ⎦⎥ = R7 250 071,51 99 – R1 251 189,89 99 = 5 998 881,62 9 (12) 22 marks IEB Copyright © 2008 PLEASE TURN OVER GRADE 12 EXAMINATION: ADVANCED PROGRAMME MATHEMATICS – MARKING GUIDELINES Page 14 of 18 QUESTION 3 3.1 3.2 99 9 9 9 999 60 59 58 ⎛ 0,16 ⎞ ⎛ 0,16 ⎞ ⎛ 0,16 ⎞ 25000⎜1 + ⎟ + 25000⎜1 + ⎟ + 25000⎜1 + ⎟ = R 163860,42 12 ⎠ 12 ⎠ 12 ⎠ ⎝ ⎝ ⎝ 9 9 ⎡ ⎛ 0,16 ⎞ 58 ⎤ ⎟ − 1⎥ 9 ⎢ ⎜1 + 12 ⎝ ⎠ ⎥ 999 163860,42 = x ⎢ 0 , 16 ⎢ ⎥ ⎢ ⎥ 12 ⎣ ⎦ x = R1890,08 999 (8) (9) 17 marks QUESTION 4 4.1 132 = 30q − 3(6 ) 999 q=5 9 30 = 5(6 ) − 2 p 999 p=0 9 99 9 4.2 Tn +1 9 9 0 , 14 ⎛ ⎞ m = 100 × 1,1n + ⎜1 + ⎟Tn 9 12 ⎠ ⎝ 9 (8) (7) 15 marks IEB Copyright © 2008 Page 15 of 18 GRADE 12 EXAMINATION: ADVANCED PROGRAMME MATHEMATICS – MARKING GUIDELINES QUESTION 5 5.1 5.2 (a) Rabbits = 30, 9 Foxes = 5 9 (2) (b) No. 9 The number of rabbits and foxes are tending to a limit. 999 (4) (c) Rabbits = 55. 9 Foxes = 8 9 (2) (d) 9 9 30 < r < 55 (4) (a) (b) 9 9 4<f<8 In the pred-prey model one must include the influence of the contact 9 between rabbits and foxes. The term represents the number of rabbit deaths 9 and is a function of the product of the number of rabbits and foxes. 9 c R= 99 fb 0,048 9 = 0,12 × 0,008 = 50 9 a⎛ c ⎞ 99 ⎟ F = ⎜⎜1 − b⎝ fbK ⎟⎠ (3) 0,64 ⎛ 0,048 ⎞ ⎟ 9 ⎜1 − 0,008 ⎝ 0,12 × 0,008 × 400 ⎠ 9 = 70 = (8) 23 marks QUESTION 6 6.1 A Logistic 9 model since there is a limit 9 to the number of ants over time. 6.2 (a) (b) 2 500 99 250 ⎞ ⎛ 375 = 250 + 250r ⎜1 − ⎟ 999 ⎝ 2500 ⎠ 0,5 = 9r 9 10 r=5 9 9 (2) (2) (5) 9 marks IEB Copyright © 2008 PLEASE TURN OVER GRADE 12 EXAMINATION: ADVANCED PROGRAMME MATHEMATICS – MARKING GUIDELINES MODULE 4 Page 16 of 18 MATRICES AND GRAPHS QUESTION 1 1.1 (a) (b) 1.2 (a) (b) 1.3 9 9 Enlargement scale factor 2 99 ⎛ 2 0⎞ ⎜ ⎟ ⎝ 0 2⎠ 99 ⎛1 0 ⎞ ⎜ ⎟ ⎝1 1 ⎠ 9 9 9 9 9 Rotation –900 and stretch factor 2, parallel to x-axis. 9 9 999 2 0 0 1 ⎛ ⎞⎛ ⎞ ⎛ 0 2⎞ 9⎜ ⎟⎜ ⎟=⎜ ⎟ ⎝ 0 1 ⎠ ⎝ −1 0 ⎠ ⎝ −1 0 ⎠ 9 9 9 Shear factor 1, invariant y-axis: 99 99 ⎛ cos 60 − sin 60 ⎞ ⎛10 ⎞ ⎛⎜ 5 − 3 3 ⎞⎟ ⎜⎜ ⎟⎟ ⎜⎜ ⎟⎟ = 99 ⎝ sin 60 cos 60 ⎠ ⎝ 6 ⎠ ⎜⎝ 3 + 5 3 ⎟⎠ (4) (5) (5) (6) (6) 26 marks QUESTION 2 2.1 6 4 ⎞ ⎛9 ⎜ ⎟ cofactors : ⎜ 4 −12 −8 ⎟ 9999 ⎜ −3 −2 −16 ⎟ ⎝ ⎠ −3 ⎞ ⎛9 4 ⎜ ⎟ adj = ⎜ 6 −12 −2 ⎟ 9 ⎜ 4 −8 −16 ⎟ ⎝ ⎠ −3 ⎞ ⎛ 4 2 −1 ⎞ ⎛ 44 0 0 ⎞ ⎛9 4 ⎜ ⎟⎜ ⎟ ⎜ ⎟ ⎜ 6 −12 −2 ⎟ ⎜ 2 −3 0 ⎟ = ⎜ 0 44 0 ⎟ 9999 ⎜ 4 −8 −16 ⎟ ⎜ 0 2 −3 ⎟ ⎜ 0 0 44 ⎟ ⎝ ⎠⎝ ⎠ ⎝ ⎠ −3 ⎞ ⎛9 4 1 ⎜ ⎟ inverse = ⎜ 6 −12 −2 ⎟ 9 44 ⎜ ⎟ ⎝ 4 −8 −16 ⎠ (10) 2.2 9 99 9 99 −3 ⎞ ⎛ 3 ⎞ ⎛ 0,5 ⎞ ⎛9 4 1 ⎜ ⎟⎜ ⎟ ⎜ ⎟ 6 −12 −2 ⎟ ⎜ 4 ⎟ = ⎜ −1 ⎟ ⎜ 44 ⎜ ⎟⎜ ⎟ ⎜ ⎟ ⎝ 4 −8 −16 ⎠ ⎝ 7 ⎠ ⎝ −3 ⎠ (6) 16 marks IEB Copyright © 2008 Page 17 of 18 GRADE 12 EXAMINATION: ADVANCED PROGRAMME MATHEMATICS – MARKING GUIDELINES QUESTION 3 (1) (2) (3) Two planes parallel. 999 det = –3, so unique solution 999 det = 0, planes not parallel, so this is the one. 9999 10 marks QUESTION 4 4.1 18, since 9 edges 99 (2) 4.2 Both the vertices of order five must go to all other vertices 99hence the minimum order of any other vertex must be 2 9 (3) 4.3 One with order 5 99 four with an order of 3 99 one with an order of 1 9 (5) 10 marks QUESTION 5 5.1 B, D, H, I 99 5.2 (Chinese Postman Problem) – Recognises the need to travel a route twice 9 – (Routes B E D and I H repeated is not a minimum route) – Routes B E I 99 and D G H 99 are repeated – A solution that starts and finishes at A 99 – Every edge has been travelled at least once 99 – Solution for the shortest inspection route: e.g. A B C D E B E G D G F H G H I E I G C A 99 9 5.3 5.4 (2) (14) Summing all the edges 9 + B E I repeat + D G H repeat = 51,4 + 5,6 9+ 4,3 9 = 61,3 km 9 (4) Yes 99 BD would remove two of the vertices with odd order 9 and HI = 3,4 99 Total travelled would be shorter than before at 51,4 + 6,4 + 3,4 = 61,2 km 9 (6) 26 marks IEB Copyright © 2008 PLEASE TURN OVER GRADE 12 EXAMINATION: ADVANCED PROGRAMME MATHEMATICS – MARKING GUIDELINES Page 18 of 18 QUESTION 6 6.1 Students must demonstrate that they have used Prim's algorithm, rather than just an intuitive approach or Kruskal's algorithm – students lose 50% of the mark if they do not demonstrate use of the correct algorithm 99 1. 2. 3. 4. 6.2 E2 → Office (488 m) 99 E2 → E4 (587 m) 99 E4 → E3 (523 m) 99 Office → E1 (1514 m) 99 488 + 587 + 523 + 1514 = 3112 m 99 (10) (2) 12 marks Total: 300 marks IEB Copyright © 2008