Mathematics T 954 STPM Lapo 2010

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  • 8/3/2019 Mathematics T 954 STPM Lapo 2010

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    Mathematics T (954)

    OVERALL PERFORMANCE

    The number o candidates or this subject was 8592. The percentage o candidates who obtained a

    ull pass was 67.09%, an increase o 1.14% compared with the previous year.

    The achievement o candidates according to grades is as ollows:

    Grade A A B+ B B C+ C C D+ D F

    Percentage 8.01 7.18 9.61 11.22 11.08 10.74 9.25 3.09 3.45 3.34 23.03

    RESPONSES OF CANDIDATES

    PAPER 954/1

    General comments

    Generally, the majority o answers were well written. However, quite a number o answers were not

    well thought o and the logical sequence was not there.

    Comments on individual questions

    Question 1

    Almost all candidates were amiliar with the property log ab = log a + log b, but most o themmade mistakes as they thought that log x2 = (log x)2 and log x+ log y= 5 x+ y= 5.

    Answers: x= 27, y= 9

    Question 2

    Most candidates were able to fnd

    dudx

    and used the chain rule. However, only a ew were able to

    simpliyABBBBBu2 1 or dudx

    in terms o x correctly, and express u2 1 as a perect square. Since the

    solution required clear proo, the steps involved should have been detailed, but many candidates

    just concluded with the answer.

    Question 3

    Some candidates were aware o the condition or a convergent series which was |r|, 1, but theyailed to realise that ex. 0 or all real values o x and thus, they did not answer the frst part

    correctly. As or the second part, more than hal o candidates did not provide the exact value as

    required by the question.

    Answers: {x: x. 0}, x= ln4

    3

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    Question 4

    Most candidates were able to fnd f(x). However, the majority o candidates ailed to observe thatthe next part requires them to use answer rom the frst part. These candidates did not use the

    anti-derivative concept to obtain the answer but used integration by parts instead.

    Answers: f(x) = 1 + ln x, 2e ln e

    Question 5

    There were only a ew candidates who were able to use the defnition or A B to establish the

    proo or the frst part.

    Answer: k=2

    3

    Question 6

    Candidates could fnd the domain and range but could not gave the answer in the correct set orm,

    or vice versa. Majority o the candidates were also very weak in giving explanation and reasoning.

    Answers: D = [3, 1) (1, 2], R = (1, 2)

    Question 7

    Most candidates were able to answer the frst part, but ailed to solve the inequalityp(x) < 0 in

    the second part. Most candidates just showed that x2 4x + 5 = 0 had complex roots without

    realising that it was always positive. Some candidates just ignored the quadratic actor saying that

    it had complex roots.

    Answers: a= 9, b = 5, {x : 1

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    Question 11

    Quite a number o candidates were able to fnd the composite unction and stationary points

    correctly and to sketch the graph. However, some candidates ailed to give the overall graph and

    presented only partial sketch or incomplete graph. For example, the sketch terminated in the second

    quadrant and did not proceed to the third quadrant. As or the second part, many candidates ailed

    to sketch the graph y= 1h(x)

    correctly. As a result, they were not able to give the right answers or

    part (c). Some candidates did not give the answers in the set orm.

    Answers: (a) (x 1)3 3(x 1) + 2, (0, 4), (2, 0); (c) (i) k : k, 14 , k 0, (ii) k : k=1

    4 ,

    (iii) k : k. 14

    Question 12

    All candidates knew that P1 =1

    |P|Adj P. However, quite a number o candidates conused with

    transpose o a matrix, adjoint and coactors.

    Some candidates were weak in transorming the inormation given into a system o linear equations.

    The candidates straight away wrote the matrix equation which they inadvertently missed showing

    the transormation o worded problems into mathematical equations clearly.

    Answers: (a) |P| = 14, Adj P =2 1 5

    8 3 1

    4 5 31 2,

    17

    114

    514

    514

    47

    27

    314

    114

    3

    14

    1 2(b) (ii) x = 5 minutes, y = 8minutes, z = 10 minutes

    PAPER 954/2

    General comments

    In general, the quality o answers given was not satisactory. Candidates showed a wide range o

    mathematical abilities. Good candidates gave well-planned answers and systematic steps in their

    presentations. On the other hand, weaker candidates showed a lack o aptitude and understanding

    o the requirements o the questions.

    Comments on individual questions

    Question 1

    This question was well answered by most candidates. However, in the integration by parts, many

    candidates made a wrong choice ou anddu

    dv

    , thus making the integration more difcult to solve.

    Another common mistake was cos y dx= sin y.

    Answer: sin y = x2 ln x12

    x2 + c

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    Question 2

    Most candidates were able to answer the frst part o the question, but ailed to solve the

    second part o the question. They were conused about the maximum and minimum

    values and ailed to make use o 13 sin(q + a) + 15. Another common mistake was1

    2