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Mathematical Reasoning 56
CHAPTER 4: MATHEMATICAL REASONING
4.1: STATEMENT- is a sentence which states a definite true or false but not both- it cannot be a question (?)-
it cannot be an exclaimation (!)- it cannot be an instruction.4.1.1: Determine whether each of the following is a statement ( ) or not a statement ( ).
Example Answer Exercise Answer
1 18 is an odd number 248124 xxx
2 X + 4 642000 = 6.42 103
3 21 + 4 = 25 (2.56 104
)2
4 23 > 34 I'm good in mathematics
5 43 + 25 68 3.46 is an integer
6 All octagons have 3 edges 7 + 91
7 What is the price of the dictionary? Please try again
8 89 is a perfect square A parallelogram is a circle
9 Some even numbers can be divided by 5 ,5,4,3,2,1,04,3,1 10 Finish your mathematics` exercise 435
2 xx
6.1.2: Determine whether each of the following is true or false.
Example Answer Exercise Answer1 1 > 31 The root of x
232 is x = 3
2 81 is a perfect square 13 + 6 >10 3
3 0.0002450 = 2.45 103 )()22(22
2xxxx
4 4325 Zero is smaller than 1
5 41 is a prime number 8,6,4,2 6 All hexagons have 6 sides 11255048
7 13 is a factor of 69 Ice melts at 10oC
8 12 is multiple of 4 ,10,9,8,7,611,10 9
All sets have as its subset(5
3)
2= 2
6
10 0 x = 4 is a root of x25x + 4 = 011 What is the square root of 9? Draw a graph of y = 3x
32.
12 A parallelogram is a quadrilateral. A heptagon has nine sides.
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Mathematical Reasoning 57
6.2 QUANTIFIER ALLAND SOME
6.2.1 Based on the information given, construct a true statement using the quantifier
all or some
6.2.1 a) Exercise:
Object and property Answer (true statement)
1 Acute angle ; less than 90o All acute angles are less than 90o
2 Negative number; smaller than zero All negative numbers are smaller than zero
3 Triangle ; right-angled triangles Some triangles are right-angled triangles
4 Sets; as its subset All sets have as its subset
6.2.1 b) Exercise:
6.2.2 Based on the information given, construct a false statement using the quantifier
all or some
6.2.2 a) Example:Object and property Answer (false statement)
1 Null sets ; no elements Some null sets have no elements
2 Parallel line ; the same length All parallel lines have the same length
3 Quadrilaterals ; two parallel sides Some quadrilaterals have two parallel sides
4 Odd number ; perfect square All odd number are perfect squares
6.2.2 b) Exercise:
Object and property Answer (true statement)
1 Rhombuses ; four equal sides
2 Odd number ; prime number
3 Factor of 6 ; factor of 3
4 Isosceles triangle ; two equal sides
5 Even number ; divisible by 10
Object and property Answer (false statement)
1 Multiple of 2 ; multiple of 4
2 Orchid flower ; yellow in colour
3 Animal ; can swim
4 Human being ; heart
5 Multiples of 8 ; can be exactly divided
by 2
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Mathematical Reasoning 58
6.3: Operations on statement
6.3.1: Change the truth of each of the following statements by using the word notor no
6.3.1 a) Example:
Statement Truth
1 4 is a factor of 32 True
4 is not a factor of 32 False
2 Human being have legs True
Human being have no legs False
3 All triangles have a sum of interior angles of 180o True
Not all triangles have a sum of interior angles of 180o False
4 Rambutan have thorns False
Rambutan have no thorns True
5 12
+ 32
is more than 32
True
12 + 32 is not more than 32 False
6 Fish has fins TrueFish has no fins False
7 Mammal is warm blooded True
Mammal is not warm blooded False
8 All perfect squares are integers True
Not all perfect squares are integers False
9 56 can be exactly divided by 6 False
56 can not be exactly divided by 6 True
10 122 is equal to 144 True
122 is not equal to 144 False
6.3.1 b) Exercise:Change the truth of each of the following statements by using the word not or no
Statement Truth
1 Some even numbers are divisible by 10
2 All factors of 7 are factors of 14
3 All trapeziums have a pair of parallel lines
4 44 is a multiple of 11
52
3
100 is equal to 102
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Mathematical Reasoning 59
6 Nucleus is an organelle
7 Plants have hair roots to absorb water and minerals
8 10 and 120 are multiples of 10
9 20 is equal to 2
10 All prime numbers are not divisible by 2
6.3.2 : Forming a compound statement by combining two given statements using the wordand or or
Concept: The truth table for p andq
p Q pandq
true true true
true false false
false true false
false false false
Concept: The truthtable for p orq
6.3.2 a) Example:
Form a true statement for each of the two given statements.
(The first statement isp and the second statement is q)
Statements p q Compound statement (true statement)
1 5125;525 3 5125525 3 and @ 5125525 3 or
2 aaaa 1;1 aaoraa 11
3 100 is an even number ;
2 is a prime number
100 is an even number and 2 is a prime number @
100 is an even number or 2 is a prime number
4 baabaa ,;, baaorbaa ,,
p Q por q
true true true
true false true
false true true
false false false
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Mathematical Reasoning 60
5 6 is a factor of 12 ;
6 is a factor of 18
6 is a factor of 12 and 6 is a factor of 18 @
6 is a factor of 12 or 6 is a factor of 18
6 53 > 12 ; 24 2 = 8 53 > 12 or 24 2 = 8
7 2 m = 200 cm ; 1 m = 100 cm 2 m = 200 cm and 1 m = 100 cm
8 A triangle has 3 sides
A hexagon has 5 sides
A triangle has 3 sides or a hexagon has 5 sides
9 4 < 2 ; 8 0 = 1 4 < 2 and 8 0 = 1
10 4 + 9 = 5 ; 2 > 32 4 + 9 = 5 or 2 > 32
6.3.2 b) Exercise:Determine the truth of each of the following compound statement.
Statements p q Compound statement
1 55 < 188115 and
2 35 or 45 is a multiple of 103 4 is a factor of 24 or 30
4 A rectangle has 4 sides and a pentagon has 6 sides
5 7 is a factor of 49 and a prime number6 1
2+ 2
2= 3
2 and 3
2+ 4
2= 5
2
7 2 is equal to 20or (2 1)1
8 Some even numbers are divisible by 2 or all odd numbers are
divisible by 3
9 36 is a perfect square and a multiple of 4
10 80 is a perfect square or an even number
11 17 is a prime number and a factor of 34
12 1 m2 = 10 000 cm2or 1 cm3 = 1000 mm2
13 Ant is an insect and has 4 legs
14 The symbols and denote a null set
155 % =
20
1and
200
1%
5
1
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Mathematical Reasoning 61
6.4: Implication
ImplicationIf p, then qwherepistheantecedent and q is theconsequent.
If a compound statement consisting ofifand only if ,
we can write itstwo implications as If p, then q and If q, thenp(known as converse of an implication)
6.4.a) Example:
Write two implications from each of the following compound statements.
6.4. b) Exercise
Write two implications from each of the following compound statements.
Compound Statement Implications
a) 5 +x = 5 if and only ifx = 0 Implication 1 : If 5 +x = 5, thenx = 0
Implication 2 : Ifx = 0, then 5 +x = 5
b) PQP if and only if
PQ
Implication 1 : If PQP , then PQ
Implication 2 : If PQ , then PQP
c) xis a multiple of 4 if and
only ifx is divisible by 4
Implication 1 : Ifxis a multiple of 4, then x is divisible by 4
Implication 2 : Ifx is divisible by 4, then xis a multiple of 4
d) 331
y if and only if y = 27 Implication 1 : If 331
y , theny = 27
Implication 2 :Ify = 27, then 331
y
e) x2 = 9 if and only ifx = 3 Implication 1 : If x2 = 9, then x = 3Implication 2 : If x = 3, then x2 = 9
Compound Statement Answer
a) 10a
= 1if and only if a = 0 Implication 1 :
Implication 2 :
b)x
3
=64 if and only ifx =4 Implication 1 :
Implication 2 :
c) Abu will be punished if and
only ifhe is late to school
Implication 1 :
Implication 2 :
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Mathematical Reasoning 62
d) x + 3 =7 if and only if
x8 =18
Implication 1 :
Implication 2 :
e) BA if and only ifABA Implication 1 :
Implication 2 :
f) y24y =4 if and only if
y = 2
Implication 1 :
Implication 2 :
g)k is a perfect square if and
only if k is an integer
Implication 1 :
Implication 2 :
h) m is a negative number if andonly ifm3
is a negative number Implication 1 :
Implication 2 :
i) 101
=z
1if and only ifz =10 Implication 1 : If 10
1=z
1, then z =10
Implication 2 :
j) 5m if and only if 52 = m Implication 1 :
Implication 2 :
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Mathematical Reasoning 63
6.5: Argument
Argument is the process in making a conclusion based on two given premises.
A premise is a given statement.
There are three simple types of arguments which can be used to make a conclusion.
Argument Type IPremise 1: All A are B
Premise 2: C is A
Conclusion: C is B
Argument Type IIPremise 1: Ifp then q
Premise 2: p is trueConclusion: q is true
Argument Type IIIPremise 1: Ifp then q
Premise 2: Not q is true
Conclusion: Notp is true
6.5 a) Complete each of the following arguments.
Example Exercise
1 Premise 1: Ifm < n, then mn < 0.
Premise 2 : m < n
Conclusion: mn < 0.
Premise 1: Ifm > n then mn > 0.
Premise 2: m > n
Conclusion:
2 Premise 1 : All rectangles have four right angles
Premise 2 : ABCD is a rectangle
Conclusion : ABCD has four right angles
i.) Premise 1:..
Premise 2 : 20 is a negative number
Conclusion :20 is smaller than zero
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Mathematical Reasoning 64
ii.) Premise 1: All numbers with a last digit 0 is
multiple of 10.
Premise 2: 2340 is a number with a last digit 0
Conclusion:
3 Premise 1 : All odd numbers are not divisible by 2
Premise 2 : 23 is an odd number
Conclusion : 23 is not divisible by 2
Premise 1: Allpentagons have a sum of their
interior angles equal to 540o
Premise 2 :..
Conclusion: MNOPQ has a sum of the interior
angles equal to 540o
4 Premise 1 : If set B =, then n(B) = 0
Premise 2 : n(B) 0
Conclusion : set B
Premise 1 : Ifx + 7 = 10, then x = 3
Premise 2 : x 3
Conclusion:.
5 Premise 1 : All factors of 12 are factors of 24
Premise 2 : 4 is a factor of 12
Conclusion : 4 is a factor of 24
Premise 1: If 90o
< < 180o, then is an obtuangle
Premise 2:
Conclusion : 100o is an obtuse angle
6 Premise 1 : Ifx = - 3, thenx3
= - 27
Premise 2 :x3 -27
Conclusion: x 3
Premise 1 :If 8,6,4,2x , thenx is an evennumber
Premise 2:
Conclusion: x is not an even number
7 Premise 1: Ifx andy are odd numbers,
then the product ofx and y is an odd
numberPremise 2 : 3 and 5 are odd numbers
Conclusion : Theproduct of 3 and 5 is an odd
number
Premise 1 : If KLM is an equilateral triangle,
then KL = LM = KM
Premise 2: KLM is an equilateral triangle
Conclusion: ..
8 Premise 1 : Ifp > 3 , then 6p > 18
Premise 2 : 6p < 18
Conclusion :p < 3
Premise 1 : IfC is a subset of D, then n(C) n(
Premise 2 : n(C) > n(D)
Conclusion:
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Mathematical Reasoning 65
6.6: Deduction and Induction
6.6.1 Deduction is making a conclusion for a specific case based on given general
statements.
6.6.1 a) Example :
Make a conclusion by deduction for each of the following cases.
1 All perfect squares can be written in the form ofx2.
36 is a perfect square
Conclusion: 36 = 62.
2 The sum of the interior angles of a polygon is (n2) 180o.
Hexagon is a polygon
Conclusion : The sum of the interior angles of a hexagon is (62) 180o
= 720o
3 All sets have an empty set, as subset
Set N = 6,5
Conclusion : Set N has an empty set, as subset
4 The radius of a circle is 3 cm
The circumference of the circle with a radius of r cm is 2 rh
Conclusion : The circumference of the circle with a radius of 3 cmis 2 )3(h = h6 cm
5 All parallelograms have two pairs of parallel lines.
ABCD is a parallelogram
Conclusion : ABCD has two pairs of parallel lines
6.6 b) Exercise
Make a conclusion by deduction for each of the following cases.
1 It is compulsory for all form 5 students to sit for the SPM examination.
Ali sat for the SPM examination.
Conclusion:.
2 All herbivores eat grass
Goats are herbivores
Conclusion: .
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Mathematical Reasoning 66
3 All cuboids have 12 edges.
Object D is a cuboid
Conclusion:..
4 All quadratic equations have 2 as the highest power of the unknown.
x2 + 2x14 = 0 is a quadratic equation.
Conclusion:
5 All those who are wearing school uniforms are students.
Abu was not wearing the school uniform.
Conclusion: .
6.6.2 Induction is making generalization based on the pattern of a numerical
sequence, or specific cases.
6.6.2 a) Example:Make a conclusion by induction for each of the following cases.
1 Given 1, 7, 17, 31
and 1 = 2(1
2
)17 = 2(22)117 = 2(3
2)1
31 = 2(42)1,
...
General conclusion: 2n21 where n = 1, 2, 3, 4
2 Given 5, 11, 17, 23
and 5 = 6(0) + 5
11 = 6(1) + 517 = 6(2) + 5
23 = 6(3) + 5
..
General conclusion: 6(n) + 5, where n = 0, 1, 2, 3, .
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Mathematical Reasoning 67
3 Given 5, 11, 21, 35
and 5 = 2(1)2 + 3
11 = 2(2)2 + 3
21 = 2(3)2 + 3
35 = 2(4)2+ 3 , .. make a general conclusion and find the 9th number
General conclusion: 2(n)2
+ 3where n = 1, 2, 3, 4,.
Hence, the 9th number is 2(9)2
+ 3 = 165
6.6.2 b.) Make a conclusion by induction for each of the following cases.
1 Given 5, 14, 29, 50
and 5 = 2 + 3(1)2
14 = 2 + 3(2)2
29 = 2 + 3(3)2
50 = 2 + 3(4)2
General conclusion
2. The numerical sequence 88, 82, 72, 58, .
can be written as
88 = 902 182 = 902 4
72 = 902 958 = 902 16..
General conclusion
3 Given 2, 9, 16, 23,
And 2 = 2 + 7(0)
9 = 2 + 7(1)
16 = 2 + 7(2)
23 = 2 + 7(3)
..
General conclusion:..
4. Given 3, 24, 81, 192,
and 3 = 3(1)3
24 = 3(2)3
81 = 3(3)3
192 = 3(4)3
General conclusion :..
5 Given 1, 4, 7, 10, 13,
and 1 = 3 12
4 = 3 227 = 3 3210 = 3 4213 = 3 52
General conclusion:
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Mathematical Reasoning 68
1) i: State whether the following statement is true or false.
ii : Complete the premise in the following argument.Premise 1: If JKL is an equilateral triangle, then the value of its interior angle is 60o
Premise 2: ______________________________________________________
Conclusion: The value of the interior angle of JKL is 60o.
iii : Write down two implications based on the following sentence.
Answer:
i. .ii. Premise 2:
.
iii. Implication 1 : .
Implication II : .
2) i : Is the sentence below a statement or a non-statement ?
ii : Write down two implications based on the following sentence.
iii : Based on the information below, make a general conclusion by induction regarding the sum of
the interior angles of a triangle.
Answer:
9 > 6 and 42
= 8
x >y if and only ifx y > 0
5 is an even number
The sum of the interior angles of triangle ABC = 180o
The sum of the interior angles of triangle JKL = 180o
The sum of the interior angles of triangle PQR = 180o
PQR is a right-angled triangle if and only if PR2
= PQ2
+ QR2
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Mathematical Reasoning 69
i. .
ii. Implication 1 : .
Implication II :
iii. General conclusion :
3. a) Determine whether the following statement is true or false.
b) Write two implications from the statement given below.
c) Complete the premise in the following argument.
Premise 1 : If 2y = 10, theny = 5.
Premise 2 : ..Conclusion : 2y 10.
Answer:
a) b) Implication I:
Implication II:
c) Premise 2: ..
4. a) Complete the conclusion in the following argument.
Premise 1 : All regular hexagons have 6 equal sides.
Premise 2 : ABCDEF is a regular hexagon.
Conclusion : .
b) Make a conclusion by induction for a list of numbers 9,29, 57, 93,that follow the patternsbelow :
9 = 4(2)27
29 = 4(3)2757 = 4(4)27
93 = 4(5)27
c) Combine the two statements given below to form a true statement.
34
= 12 or4
5= 1.25
x = 4 if and only ifx3 = 64
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Mathematical Reasoning 70
i) 15 (5) =5ii) 32 is a multiple of 8.
Answer:
a.) Conclusion:
b.) .
c.) ..
5. a) Below are three statements : 42 = 8
: 75.04
3
: 5 6 if and only if r> 2
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Mathematical Reasoning 71
SPM PAST YEAR QUESTIONS
Year 2003 (Nov)
a) Is the sentence below a statement or non-statement?
4 is a prime number
b) Write down two implications based on the following sentence;
'' PRifonlyandifRP
c) Based on the information above, make a general conclusion by induction regarding the number of
subsets in a set with k elements. (5 marks)
Answer : a) Statement
b) Implication 1 : If RP , then '' PR Implication 2 : If '' PR , then RP
c) The number of subsets in a set with k elements is 2k
Year 2004 (July)
a) State whether the following sentence is a statement or a non-statement.
b.) Write down a true statement using both of the following statements:
Statement 1: 1052
Statement 2: 1001010
c.) Write down two implications based on the following sentence:
(4 marks)
Answer : a) Statement
b) 52 = 10 or 10 x 10 = 100c) Implication 1 : If y < x then -y > -x
Implication 2 : If -y > -x then y < x
The number of subsets in a set with 2 elements is 22.
The number of subsets in a set with 3 elements is 23.
The number of subsets in a set with 4 elements is 24.
All multiples of 2 are divisible by 4.
y < x if and only ify > -x
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Mathematical Reasoning 72
Year 2004 (Nov)
a) State whether the following statement is true or false.
b) Write down two implications based on the following sentence
c) Complete the premise in the following argument :
Premise 1 : All hexagons have six sides.
Premise 2 : .Conclusion : PQRSTU has six sides. (5 marks)
Answer : a) Trueb) Implication 1 : If m3 = 1000 then m = 10
Implication 2 : If m = 10 then m3 = 1000
c) PQRSTU is a hexagon
Year 2005 (July)
a) Determine whether the following sentence is a statement or non-statement.
b) Write down the converse of the following implication, hence state whether the converse is true or false.
a) Make a general conclusion by induction for a list of number 3, 17, 55, 129, which follows the followingpattern:
(5 marks)
8 > 7 or 32 = 6
m3 = 1000 if and only if m = 10
03522 mm
If x is an odd number then 2x is an even number.
1)4(21291)3(255
1)2(217
1)1(23
3
3
3
3
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Mathematical Reasoning 73
Year 2005 (Nov)
a) State whether each of the following statement is true or false.
i) 8 2 = 4 and 82 = 16.
ii) The elements of set A = 18,15,12 are divisible by 3 or the elements of set B = 8,6,4 are multiples of 4.
b) Write down premise 2 to complete the following argument .
Premise 1 :Ifx is greater than zero, thenx is a positive number.
Premise 2 : .Conclusion : 6 is a positive number.
c) Write down 2 implications based on the following sentence.
3m > 15 if and only if m > 5
Implication 1 :
Implication 2 : (5 marks)
Year 2006 (July)
a.) State whether each of the following statements is true or false.(i) 464
3
(ii.) -5 > - 8 and 0.03 = 3 1
10
b) Write down two implications based on the following sentence.
ABC is an equilateral triangle if and only if each of the interior angle of ABC is 600.
c.) Complete the premise in the following argument:
Premise 1 : .
Premise 2 : .1809000 x
Conclusion : sin0
x is positive. (5 marks)
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Mathematical Reasoning 74
Year 2006 (Nov)(a) Complete each of the following statements with the quantifier all or some so that it will become
a true statement
(i) of the prime numbers are odd numbers.(ii) ... pentagons have five sides.
(b) State the converse of the following statement and hence determine whether its converse is true or false.
(c) Complete the premise in the following argument:Premise 1 : If set K is a subset of set L, then LLK
Premise 2 :
Conclusion: Set K is not a subset of set L
Year 2007 (June)
a) State whether the following statement is true or false.b) Write down Premise 2 to complete the following argument:
Premise 1 : If a quadrilateral is a trapezium, then it has two parallel sides.
Premise 2 : ..
Conclusion: ABCD is not a trapezium.
c) Based on the information below, make a general conclusion by induction regarding the
sum of interior angles of a polygon with n sides.
c) Write down two implications based on the following statement: Matrix
dc
bahas an inverse if and only if adbc 0
[6 marks]
Some even numbers are multiples of 3
Sum of interior angles of a polygon with 3 sides is ( 32 ) x 1800
Sum of interior angles of a polygon with 4 sides is (42 ) x 1800
Sum of interior angles of a polygon with 5 sides is (52 ) x 1800
If x > 9 , then x > 5
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Mathematical Reasoning 75
Year 2007 (Nov)
a) Complete the following statement using quantifier all or some, to make it a true statement.
b) Write down Premise 2 to complete the following argument:Premise 1 : If M is a multiple of 6, then M is a multiple of 3.
Premise 2 : ..
Conclusion : 23 is not a multiple of 6.
c) Make a general conclusion by induction for the sequence of numbers 7, 14, 27, which follows the following pattern.
7 = 3(2)1 + 1
14 = 3(2)2
+ 2
27 = 3(2)3 + 3
=
d) Write down two implications based on the following statement: p q > 0 if and only if p > q
Implication 1 :
Implication 2 : ...[6 marks]
Year 2008 (June)
a) State whether the following compound statement is true or false.
7 x 7 = 49 and (-7)2
= 49
................................quadratic equations have two equal roots.
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Mathematical Reasoning 76
b) Write down two implications based on the following compound statement:
c) Write down Premise 2 to complete the following argument:Premise 1:
If PQRS is a cyclic quadrilateral, then the sum of the interior opposite angles of PQRS is1800 .
Premise 2:
Conclusion:
PQRS is not a cyclic quadrilateral.
[5 marks]
Year 2008 (Nov)
a) State whether the following compound statement is true or false:
b) Write down two implications based on the following compound statement:
c) It is given that the interior angle of a regular polygon of n sides is 21 180n
.
Make one conclusion by deduction on the size of the interior angle of a regular hexagon.
KLM is an isosceles triangle if and only if two angles in KLM are equal.
53 = 125 and -6 < -7
x3
= -64 if and only if x = -4.
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Mathematical Reasoning 78
6.3.2 b
p q True / False
1 False
2 False3 True
4 False
5 True
6 False
7 True
8 False
9 True
10 True
11 True
12 True
13 False14 True
15 False
6.4. b
a Implication 1 : If 10a
= 1, then a = 0Implication 2 : If a = 0, then 10
a= 1
b Implication 1 : Ifx3
=64, thenx =4
Implication 2 : Ifx =4, then x3
=64
c Implication 1 : If Abu is punished, then he was late to school
Implication 2 : If Abu is late to school, then he will be punished
d Implication 1 : If x + 3 =7, then x8 =18Implication 2 : If x8 =18, then x + 3 =7
e Implication 1 : If BA , then ABA
Implication 2 : If ABA , then BA
f Implication 1 : Ify24y =4 then y = 2
Implication 2 : Ify = 2, then y24y =4
g Implication 1 : Ifk is a perfect square, then k is an integer
Implication 2 : If k is an integer, thenk is a perfect square
h Implication 1 : If m is a negative number, then m3
is a negative number
Implication 2 : If m3
is a negative number, then m is a negative number
i Implication 1 : If 10 1 =z1 , then z =10
Implication 2 : Ifz =10, then 101
=z
1
j Implication 1 : If 5m , then 52
= m
Implication 2 : If 52
= m, then 5m
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Mathematical Reasoning 79
6.5 b
6.6.1 b
6.6.2 b
Questions According to Examination Format
1. i: False
ii : JKL is an equilateral triangle.
iii : Ifx >y, thenx y > 0 .Ifx y > 0, thenx >y.
2. i : Statement
ii : 1 : If PQR is a right-angled triangle, then PR2
= PQ2
+ QR2
2: If PR2
= PQ2
+ QR2, then PQR is a right-angled triangle
iii : The sum of the interior angles of all triangles = 180o
3. a) True
b) Ifx = 4, then x3
= 64If x3 = 64, then x = 4
c) y 5
4. a) ABCDEF has 6 equal sides.
1 Premise 2 : 5 < 12
2 i.)Premise 1 : All negative numbers are smaller than zeroii.)Premise 2 : 2340 is a multiple of 10
3 Premise 2 : MNOPQ is a pentagon
4 Conclusion : x + 5 10
5 Premise 2 : 90o
2 , then 3r > 6.
PAST YEARS SPM QUESTIONS
June 2004
1. a) Statementb) 105
2 or 1001010
c ) If y < x , then xy
If xy , then xy
Nov 2004
2. a) True
b) If m3 = 1000 , then m = 10
If m = 10, then m3 = 1000
c) PQRSTU is a hexagon.
June 2005
3. a) Statementb) If 2x is an even number, the x is an odd number. (True)
c) ,123 n where n = 1, 2, 3
Nov 2005
4. a) i: False
ii: True
b) 6 is greater than zero.
c) If 3m > 15, then m > 5.
If m > 5, then m > 5.
June 2006
5. a) (i) True(ii) False
b) If ABC is an equilateral triangle, then each of the interior angle of ABC is 600.
If each of the interior angle of ABC is 600, then ABC is an equilateral triangle.
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8/2/2019 Chapter 6 II Math Reasoning ENHANCE_edit
26/26
c) If00
18090 x , then 0sin x is positive.
7. Nov 2006a) (i) Some
(ii) All
b) If x > 5 , then x > 9 , False
c) LLK
8. June 2007
a)Trueb)ABCD has no two parallel sidesc)(n2 ) x 1800d) Implication 1 : If matrix
dc
bahas an inverse then adbc 0
Implication 2 : If adbc 0 then
dc
bahas an inverse
9. Nov 2007
a)Someb)23 is not a multiple of 3c)3(2)n + n , n = 1, 2, 3, d)Implication 1 : If pq > 0 then p > q
Implication 2 : If p > q then pq > 0
10. June 2008a) Trueb) Implication 1 : If KLM is an isosceles triangle, then two angles in
KLM are equals.Implication 2 : If two angles in KLM are equals, then KLM is an
isosceles triangle.
c) The sum of the interior opposite angles of PQRS is not equal to 1800.11. Nov 2008
a) Falseb) Implication 1 : If x3 = -64 then x = -4
Implication 2 : If x = -4 then x3
= -64