w w ap eP m e tr .X w CAMBRIDGE INTERNATIONAL EXAMINATIONS om .c s er Cambridge International General Certificate of Secondary Education MARK SCHEME for the October/November 2014 series 0606 ADDITIONAL MATHEMATICS 0606/11 Paper 1, maximum raw mark 80 This mark scheme is published as an aid to teachers and candidates, to indicate the requirements of the examination. It shows the basis on which Examiners were instructed to award marks. It does not indicate the details of the discussions that took place at an Examiners’ meeting before marking began, which would have considered the acceptability of alternative answers. Mark schemes should be read in conjunction with the question paper and the Principal Examiner Report for Teachers. Cambridge will not enter into discussions about these mark schemes. Cambridge is publishing the mark schemes for the October/November 2014 series for most Cambridge IGCSE®, Cambridge International A and AS Level components and some Cambridge O Level components. ® IGCSE is the registered trademark of Cambridge International Examinations. Page 2 Mark Scheme Cambridge IGCSE – October/November 2014 1 dy 16 = 2x − 2 dx x When M1 A1 dy = 0, dx DM1 x = 2, y = 12 2 (a) 4 Paper 11 for attempt to differentiate all correct dy for equating to zero and an dx attempt to solve for x. A1 A1 for both, but no extra solutions B1 for correct shape B1 for max value of 2, starting at (0, 2) and finishing at ( 180o , 2) B1 for min value of –4 B1 must be positive y 3 2 Syllabus 0606 2 1 x 1 2 3 −1 −2 −3 -4 −4 (b) (i) (ii) 3 (i) 4 60o or π or 1.05 rad 3 1 y = 4(x + 3) 2 (+ c ) 1 10 = 4 9 2 + c c = −2 1 y = 4(x + 3) 2 − 2 (ii) B1 1 1 M1, A1 M1 for (x + 3) 2 , A1 for 4(x + 3) 2 M1 for a correct attempt to find c, but must be from an attempt to integrate A1 Allow A1 for c = –2 1 6 = 4(x + 3) 2 − 2 x =1 A1 ft ft for substitution into their equation to obtain x; must have the first M1 © Cambridge International Examinations 2014 Page 3 4 Mark Scheme Cambridge IGCSE – October/November 2014 (i) 5y2 − 7 y + 2 = 0 B1, B1 (ii) (5 y − 2)( y − 1) = 0 M1 (i) x = −0.569 A1 must be evaluated to 3sf or better y = 1, x = 0 B1 1 dy = 3x 2 − x dx M1 for attempt to differentiate B1 for y = 1 dy =2 dx Tangent: y − 1 = 2(x − 1) 6 (i) B1 for 5, B1 for –7 M1 2 ln 0.4 ,x= 5 ln 5 When x = 1, y = 1 and (ii) Paper 11 for solution of quadratic equation from (i) for use of logarithms to solve equation of the type 5 x = k y= 5 Syllabus 0606 DM1 ( y = 2 x − 1) A1 Mid-point (5, 9) B1 9 = 2(5) − 1 B1 Alternative Method: Tangent equation y = 2 x − 1 Equation of line joining (–2, 16) and (12, 2) y = − x + 14 Solve simultaneously x = 5, y = 9 B1 Mid-point (5, 9) B1 (2 + px )6 = 64 + 192 px + 240 p 2 x 2 … B1 for attempt to find equation of tangent allow equation unsimplified for midpoint from given coordinates for checking the mid-point lies on tangent for a complete method to find the coordinates of the point of intersection for midpoint from given coordinates for 240p2 or 240p2x2 or 2 6 C 2 × 2 4 × ( px ) or 6 C 2 × 2 4 × p 2 or 6 C 2 × 2 4 × p 2 x 2 240 p 2 = 60 1 p= 2 (ii) M1 A1 (3 − x )(64 + 192 px + 240 p 2 x 2 ...) Coefficient of x2 is 180 − 192 p = 84 B1 ft M1 A1 for equating their term in x2 to 60 and attempt to solve ft for 192p, 96 or 192 × their p for 180 – 192p © Cambridge International Examinations 2014 Page 4 7 (i) (ii) Mark Scheme Cambridge IGCSE – October/November 2014 A −1 = 1 b −2b 5ab a 3a X = BA −1 1 −a b 5a = 2a 2b 1 5b 0 = 4 5 8 (i) (ii) 2 5a 3 5b − 1 2 5 uuur 12 1 AB = , at P, x = −2 + (12) 4 16 so at P , x = 1 1 y = 3 + (16 ) , y = 7 4 Gradient of AB = Perp line: (iii) B1, B1 16 3 , so perp gradient = − 12 4 3 (x − 1) 4 (3x + 4 y = 31) y−7 = − 31 Q 0, 4 Area AQB = 12.5 Syllabus 0606 B1 for 1 , B1 for 5ab Paper 11 b − 2b a 3a M1 for post-multiplication by inverse matrix DM1 for correct attempt at matrix multiplication, needs at least one term correct for their BA −1 (allow unsimplified) A1 A1 for each correct pair of elements, must be simplified B1 for convincing argument for x = 1 B1 for y = 7 M1 for finding gradient of perpendicular M1 for equation of perpendicular through their P A1 Allow unsimplified B1 ft M1 A1 ft on their perpendicular line, may be implied for any valid method of finding the area of the correct triangle, allow use of their Q; must be in the form ( 0, q ) . © Cambridge International Examinations 2014 Page 5 9 (i) Mark Scheme Cambridge IGCSE – October/November 2014 log y = log a + x log b x 2 2.5 3 3.5 4 lg y 1.27 1.47 1.67 1.87 2.07 lny 2 2.93 2.5 3.39 3 3.84 logy 3 3.5 4.31 B1 for the statement, may be seen or implied in later work, M1 for attempt to draw graph of x against log y A2,1,0 –1 each error in points plotted DM1 for attempt to find gradient and equate it to log b, dependent on M1 in (i) 2 1 x (ii) 2 3 4 x Gradient = log b lg b = 0.4 or ln b = 0.92 b = 2.5 (allow 2.4 to 2.6) A1 Intercept = log a lg a = 0.47 or ln a = 1.10 DM1 a = 3 (allow 2.8 to 3.2) A1 Alternative method: Simultaneous equations may be used provided points that are on the plotted straight line are used. a = 3 (allow 2.8 to 3.2) b = 2.5 (allow 2.4 to 2.6) Paper 11 4 4.76 y 1 Syllabus 0606 DM1 DM1 A1 A1 for attempt to equate y-intercept to log a or use their equation with their gradient and a point on the line, dependent on M1 in (i) for a pair of equations using points on the line, dependent on M1 in (i) for solution of these equations, dependent on M1 in (i) A1 for each © Cambridge International Examinations 2014 Page 6 10 (a) (i) (ii) (iii) (b) (i) (ii) Mark Scheme Cambridge IGCSE – October/November 2014 C5 × 12C5 B1, B1 B1 4 places are accounted for Gender no longer ‘important’ M1 for realising that 4 places are accounted or that gender is no longer important A1 for 8008 M1 for at least 5 of the 7 cases, allow unsimplified 16 C6 = 8008 Alternative Method 6 C6 × 10C0 + 6C5 × 10C1 ( ) ( ) ... ( 6C0 × 10C6 ) 1 + 60 + 675 + 2400 + 3150 + 1512 + 210 = 8008 cos 3 x =0 sin 3 x 1 cos 3x 2 − =0 sin 3x 2 cos 3 x − 1 sin 3 x = , 3 x = 30o , 150o 2 x = 10o , 50o 1 π cos y + = − 2 2 π 2π 4π , y+ = 2 3 3 so y = for use of cot 3 x = cos3 x , may be sin 3 x implied x = 30o , 90o and A1 M1 Leading to cos 3 x = 0, 3 x = 90o , 270o (b) B1 for each, allow unevaluated with no extra terms Final answer must be evaluated and from multiplication 56 × 792 = 44352 Need 11 (a) Paper 11 B1 B1 B1 360 60 36 8 Syllabus 0606 DM1 A1 DM1 for attempt to solve sin 3 x = A1 correctly to obtain x A1 for both, condone excess solutions M1 DM1 π 5π (0.524, 2.62) , 6 6 for attempt to solve cos 3x = 0 correctly from correct factorisation to obtain x A1 for both, no excess solutions in the range 1 2 π for dealing with sec y + 2 correctly for correct order of operations, must not mix degrees and radians A1, A1 © Cambridge International Examinations 2014 Page 7 Mark Scheme Cambridge IGCSE – October/November 2014 12 (i) uuur AQ = λ b − a B1 (ii) uuur BP = µ a − b B1 (iii) (iv) (v) uuur 1 2 OR = a + ( λ b − a ) or λ b − ( λ b − a ) 3 3 2 1 = a + λb 3 3 uuur 7 1 OR = b + ( µ a − b ) or µ a − ( µ a − b ) 8 8 1 7 = b + µa 8 8 2 1 1 7 a + λb = b + µa 3 3 8 8 2 7 16 Allow 0.762 = µ, µ = 3 8 21 3 1 1 Allow 0.375 λ = ,λ = 8 3 8 Syllabus 0606 Paper 11 1 their (i) 3 M1 for a + A1 Allow unsimplified M1 for b + A1 Allow unsimplified M1 for equating (iii) and (iv) and then equating like vectors A1 A1 © Cambridge International Examinations 2014 7 their (ii) 8