http://sahatmozac.blogspot.com ADDITIONAL MATHEMATICS MODULE 1 FUNCTIONS Organized by Jabatan Pelajaran Pulau Pinang 2006 http://mathsmozac.blogspot.com http://sahatmozac.blogspot.com CHAPTER 1 : FUNCTIONS Contents 1.1 Concept map Page 2 1.2 Determine domain , codomain , object, image and range of relation 3 1.3 Classifying the types of relations 3 2.1 Recognize functions as a special relation. 2.2 Expressing functions using function notation. 2.3 Determine domain , object , image and range 4-5 3.0 Composite Functions 6 -9 4.0 SPM Questions 9 – 10 5.0 Assessment test 11 – 12 6.0 Answers 13 – 14 http://mathsmozac.blogspot.com 1 http://sahatmozac.blogspot.com CONCEPT MAP FUNCTIONS Relations Object images ………….,, …………… …………… Functions Function Notation Type of relation y Or ……………… Composite Functions Inverse Functions f: x One to one Many to one ……….. fg ( x ) = ……………. Object f(x)=y ……………… http://mathsmozac.blogspot.com 2 http://sahatmozac.blogspot.com 1.1 Functions Express the relation between the following pairs of sets in the form of arrow diagram, ordered pair and graph. Arrow diagram Ordered pair Graph a ) Set A = Kelantan, Perak , Selangor Set B = Shah Alam , Kota Bharu ,Ipoh Relation: ‘ City of the state in Malaysia ‘ b )Set A = triangle,rectangle, pentagon Set B = 3,4,5 Relation : ‘ Number of Sides’ 1.2 Determine domain , codomain , object, image and range of relation. List down the domain , codomain , objects , images and the range of the following relation . 3 9 2 5 1 4 -2 3 -3 1 Set P Diagram 1 Set Q Domain = ……………………………………… Codomain = ……………………………………… Object =…………………… Image =…………………… Range =…………………... http://mathsmozac.blogspot.com 3 http://sahatmozac.blogspot.com 1.3 Classifying the types of relations State the type of the following relations a) x 2 x 3 4 2 9 16 4 x X 4 2 -2 -3 36 6 …………………………………………….. c) x b) x X2 …………………………………………. Type of number d) 3 4 2 -3 4 Prime 9 Even -3 9 …………………………………………….. …………………………………………… 2.0 Functions 2.1 Recognize functions as a special relation. 2.2 Expressing functions using function notation. 2.3 Determine domain , object , image and range 2.1 Identify each of the following relations is a function or not. a) A B A B b) p 1 q 2 r 3 A B c) p a a p q b b q r c c r d …………………………… …………………………… …………………………… http://mathsmozac.blogspot.com 4 http://sahatmozac.blogspot.com 2.2 Express each of the following functions using function notation. a) A B 2 b) A B 4 2 3 6 4 8 Function notation f : x …………….. or f ( x ) = …………… c) A B 4 1 5 3 9 2 7 4 16 3 9 Function notation g : x …………….. or g ( x ) = …………… Function notation h : x …………….. or h ( x ) = …………… 2.3 a)Find the image for each of the following functions. ( i ) f : x 2x + 9 ( ii ) f : x f (5 ) = 5x 3 2 x +6 5 find h ( -2 ) iii) h : x f (-3 ) = ………………………… ………………………… ………………………….. b ) Find the object for each of the following functions. i )f : x 2x – 3 , find the object when the image is 5. 2x 8 , find the 3 object when the image is 3. ii )f : x 6 – 7 , find the x object when the image is -5. i )f : x http://mathsmozac.blogspot.com 5 http://sahatmozac.blogspot.com c ) Find the value of x for each of the following function. 8 2x 1 for which g (x) = 4 ii ) i ) f ( x ) = 2x + 7 for which f ( x ) = 3 g(x)= iii) x 3 2 for which h ( x ) = x h(x) = 3.0 Composite Functions g f a b c fg f: a b g: b c gf : a c 3.1 ( a ) Find the value for each of the following composite functions i ) f( x ) = x + 2 and g ( x) = 5x + 3 find fg ( 2 ) = ii ) g ( x ) = 2 +5x iii) f(x) = 3x+ find g2(4) = 1 and g ( x ) 2 1 .Find fg ( 1 ) x 1 http://mathsmozac.blogspot.com 6 http://sahatmozac.blogspot.com ( b ) Find the following composite function. ( i ) f( x ) = 2x + 3 g( x ) = 1 – x fg ( x ) = ( ii ) f( x ) = 2x + 3 g( x ) = 2 + 5 x2 gf ( x ) = ( iii ) f ( x ) = 1 g(x)= x 2 4 x fg ( x ) = ( c) Find the value of x for each of the following composite function. 3 x g ( x ) = 2x + 1 i) f ( x ) = fg ( x ) = 5 ii )f( x ) = 2x + 4 iii) f ( x ) = 1 - g ( x ) = x -2 g (x ) = fg ( x ) = 2 4 x fg ( x ) = -1 http://mathsmozac.blogspot.com 7 x , 2 http://sahatmozac.blogspot.com ( d ) Solve i )Given the function f: x 4x + k , g : x x – 2 fg : x mx + 8 ii )Given the function f: x 9 – 2x , g : x ax + b and fg: x 1 – 6x iii)Given the function f: x 2x – 1 , g : x 4x and gf : x ax + b Find the value of k and m Find the value of a and b. Find the value of a and b http://mathsmozac.blogspot.com 8 http://sahatmozac.blogspot.com 4.0 SPM QUESTIONS SPM 2004 ( paper 1, question no 1 ) 1. Diagram 1 shows the relation between set P and set Q w d x e y f z Set P Set Q Diagram 1 State ( a ) the range of the relation, ( b ) the type of relation. Answer: http://mathsmozac.blogspot.com 9 [2 marks] http://sahatmozac.blogspot.com SPM 2004 ( paper 1, question no 3) 1. Given the function h ( x ) = 6 , x 0 and the composite function hg ( x ) = 3x , find x (a)g(x) ( b ) the value of x when gh ( x ) = 5. Answer: http://mathsmozac.blogspot.com 10 [ 4 marks] http://sahatmozac.blogspot.com SPM 2005 Question 1. In Diagram 1 , the function h maps x to y and the function g maps y to z. x y h g z 8 5 2 Diagram 1 Determine ( a ) gh ( 2 ) Answer: http://mathsmozac.blogspot.com 11 http://sahatmozac.blogspot.com 5.0 Assessment( 30 minutes) 1) P a q b r c s A Diagram 1 B The diagram above shows the relation between set A and set B. State a) the type of relation b) the range of relation Answer: 2) Given that f : x 2x + 7 find the object when image is 3. Answer: 3) Given that f ( x ) = 10 – kx and f ( 2 ) = 4 ( k constant ) . Find the value of k. Answer: http://mathsmozac.blogspot.com 12 http://sahatmozac.blogspot.com 4) Given that f ( x ) = 4x -1 and g ( x ) = 2x + 3 . Find i ) fg ( x ) ii ) fg ( - 2 ) Answer: 5 ) Given the function f : x px + 2 and g : x qx + 3 . If the composite function fg is such that fg ( x ) = 8x + 8 , find the values of p and q. Answer: http://mathsmozac.blogspot.com 13 http://sahatmozac.blogspot.com 6.0 ANSWERS 1.1 Arrow diagram Ordered pair KB Kel SA Sel (kel, kb), (Sel, S.Alam), ( Perak,Ipoh) Ipoh Per A Graph KB SA Ipoh B Kel 3 Tri (Tri, 3), (rec, 4), ( Pen,5) 43 rec Per 5 4 5 Pen Sel 3 A B Pen rec Tri 1.3 Domain = -3,-2,1,2,3 , codomain = 1,3,4,5,9 , Object =1,2,3,-2,-3 Image = 1,3,4,5,9 , Range = 1,4,9 ( a ) one to one ( b ) One to many( c ) many to one( d ) many to many 2.1 ( a ) function 2.2 (a) 2x (b) x2 (c) 2x + 3 2.3 a) ( I ) 19 (ii) -6 (iii ) 3 3.1 a) ( i) 15 (ii ) 102 b) (i) 5 – 2x (ii) 20x2+60x+47 1.2 ( b ) Not function 1 (ii) 1 5 d) (i) k=16,m=4 c) (i) - 4.0 SPM QUESTIONS SPM 2004( P1,Q1) a) SPM 2004( P1,Q3) SPM 2005( P1,Q1) ( c ) function b) (i) 2 (ii) 1 1 (iii) 3 c) (i) -2 (ii) (iii) -3 2 2 ( iii) 2 (iii) 1- 2 x (iii) 1 (ii) a=3,b=4 (iii) a=8,b= - 4 range = x,y (a) g(x) = 2 , x 0 3 b )many to one ( b) x = 15 8 http://mathsmozac.blogspot.com 14 http://sahatmozac.blogspot.com 5.0 Assessment( 30 minutes) 1) ( a)many to many 2) -2 3) k=3 4) (i) 8x+11 (ii) -5 1 p = , q = 16 2 5) ( b ) range = p,q,r http://mathsmozac.blogspot.com 15 http://sahatmozac.blogspot.com ADDITIONAL MATHEMATICS MODULE 2 FUNCTIONS http://mathsmozac.blogspot.com 16 http://sahatmozac.blogspot.com CHAPTER 1 : FUNCTIONS Contents Page 1.0 Inverse Functions ( concept map ) 2–4 2.0 Absolute Function 4-6 3.0 SPM Questions 7–8 4.0 Assessment ( 30 minutes ) 9 – 10 5.0 Answers 11 – 13 http://mathsmozac.blogspot.com 17 http://sahatmozac.blogspot.com CHAPTER 1 : FUNCTIONS FUNCTIONS Ordered pairs Arrow diagram Relations Functions graph Object images Domain Codomain , Range Function Notation Type of relation f: x y Or f(x) = y One to one Many to one image Inverse Functions Composite Functions fg ( x ) = f [ g(x) ] Object One to many Many to many f(x)=y f-1( y ) = x 1.0 Inverse Functions 1.1 Determine the object by inverse mapping 1.2 Determine the inverse functions a ) Find the inverse function of each of the following functions. x ii) f ( x ) = i)f(x)=x+3 5 http://mathsmozac.blogspot.com 18 iii ) f ( x ) = 3x 1 2 http://sahatmozac.blogspot.com iv ) f ( x ) = 7 – 5x v)f(x)= 3 x 4 vi ) f( x ) = 5 4x 3 b ) Find the inverse function of each of the following functions in terms of p and q i ) f ( x ) = px - q ii ) f ( x ) = x p q http://mathsmozac.blogspot.com 19 iii) f ( x ) = px + 1 q http://sahatmozac.blogspot.com c ) Given the function f : x x2 , x 1 and g(x) =2x -6 , find f-1 g . x 1 Answer: d ) Inverse function f is define by f-1 : x x 5 1 , x . Find f ( 2 ) 2x 1 2 Answer: 2.0 Absolute Function 1. Sketch the graph of each of the following functions a)f(x)=x b)f(x)=x+1 http://mathsmozac.blogspot.com 20 http://sahatmozac.blogspot.com c) f (x ) = | x | d)f(x)=|x+1| e ) f (x) = |x| + 1 f)f(x)=|x|-1 2.Sketch the graph of each the following functions and state the corresponding range. a) f : x 2x – 3 for 0 x 4 b) f : x |2x – 3| for 0 x 4 f(x) f(x) Range :………………………………. Range : ………………………………………… http://mathsmozac.blogspot.com 21 http://sahatmozac.blogspot.com c) f : x | 5 – 2x |for -1 x 4 d) f : x |9 – 2x| for 0 x 6 f(x) Range :………………………………. Range :………………………………. e) f : x |2x| – 1 for -1 x 3 f ) f : x | 3x | for -2 x 2 Range :………………………………. Range :………………………………. http://mathsmozac.blogspot.com 22 http://sahatmozac.blogspot.com 3.0 SPM QUESTIONS SPM 2004 Question. 1. Given the functions h : x 4x + m and h-1 : x 2kx + 5 , where m and k are 8 constants, find the value of m and of k. [ 3 marks] Answer: SPM 2005 ( Paper 1, Question 1 ) 2. In Diagram 1 , the function h maps x to y and the function g maps y to z. x y h g z 8 5 2 Diagram 1 Determine ( a ) h-1 ( 5 ) Answer: http://mathsmozac.blogspot.com 23 http://sahatmozac.blogspot.com SPM 2005 ( Paper 1, Question 2 ) 1.The function w is defined as w ( x ) = ( a ) w-1 ( x ), ( b ) w-1 ( 4 ). Answer: 5 , x 2. 2 x [ 3 marks] SPM 2005 ( Paper 1, Question 3 ) 1.The following information refers to the functions h and g. h: x g: x 2x – 3 4x - 1 Find gh-1 ( x ). [ 3 marks] http://mathsmozac.blogspot.com 24 http://sahatmozac.blogspot.com 4.0 Assessment ( 30 minutes ) 1.A function f is defined by f: x 6 Find a)f(x) 1 x 2 b ) f-1 ( 5 ) Answer: 2. Inverse function f is defined by f-1 : x 5 4x 3 find f ( 2 ). Answer: http://mathsmozac.blogspot.com 25 http://sahatmozac.blogspot.com 3.Given the function f : x 2x - m and inverse function f-1 : x nx + 7 3 Find the value of m and n. Answer: 4. Sketch the graph of the function f ( x ) = |2x – 5 | for 0 x 6. Hence , state the corresponding range. Answer: http://mathsmozac.blogspot.com 26 http://sahatmozac.blogspot.com 5.0 ANSWERS 1.1 2x 1 7x 5 3x (iv) (v) 3 – 4x (vi) 3 5 4 xq x 1 (b) (ii ) xq + p (iii) p p pq 2x 4 7 ( c) , x 7 2x 2 ( d ) -1 ( a )( i) x- 3 ( ii) 5x (iii) Absolute function f(x) a) f(x) b) _1 | -1 x f(x) c) x f(x) d) _1 | -1 x f(x) e) x f(x) f) _1 | -1 | -1 x _ -1 | 1 x | 1 | 2 x 2. a) f(x) b) _8 _ . f(x) _5 | 1 | 2 x -3 3 f ( x) 8 0 f(x) 5 http://mathsmozac.blogspot.com 27 http://sahatmozac.blogspot.com c) f(x) _7 f(x) d) _9 | 2 | 4 | 3 x 0 f(x) 7 0 f(x) 9 f(x) _5 e) | 5 x f(x) _6 f) _1 | -1 | _ -1 1 | 3x -1 f(x) 5 | -2 | 2 0 f(x) 6 SPM 2004 ( P1,Q2) 1 5 K= , m=8 2 SPM 2005 ( P1,Q2) (a) 2 SPM 2005 ( P1,Q2) 2x 5 3 (a) , x 0 ( b ) x 4 SPM 2005 ( P1,Q3) 2x+ 5 Assessment ( 30 minutes ) 1)( a) 12 – 2x ( b ) 8 1 2) 4 1 3) n = , m=7 2 4) http://mathsmozac.blogspot.com 28 x http://sahatmozac.blogspot.com a) f(x) _7 _5 | 2 | 3 | 6 x The corresponding range of f(x ) = 0 f(x) 7 http://mathsmozac.blogspot.com 29