Page 16 - Spotlight A+ SPM Additional Mathematics Form 4 & 5
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Form
                                                                                                          4
                                                        Chapter 5  Progressions   Additional Mathematics


                                      1   3                      30.  It is given that the sum of the first n terms of a
                   19.  It  is  given  that  6,  7 ,  9 , …  is a geometric
                                      2   8                         geometric progression is S  =   3  [3  − 1].  C2
                                                                                                2n
                     progression. Find the minimum value of  n if                        n   8
                     the value T  > 300.   C3                       (a)  Find the sum of the first 5 terms.
                              n
                                                                    (b)  Express the  n term of the geometric
                   20.  The 2nd and 5th terms of a geometric            progression, in term of n.
                                             17
                     progression  are  10  and  19  .  Find  the  first
                                            32                   31.  Given that the sum of the first n terms of the
                     term which is more than 100.   C3              geometric progression 2, −4, 8, … is 21 846,
                                                                    find the value of n.  C2
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                   21.  Find  the  sum  of  first  terms  of  the  following
                     geometric progression.  C1                  32.  It is given the sequence 3, 1,   1  , … is a
                     (a)  1, 2, 4, …, to n = 13                                                  3
                     (b)  5, 15, …, to n = 14                       geometric progression. Find the value of
                     (c)  12, –24, 48, …, to n = 12                 n  when  the  sum  of  the  first  n terms of the
                               3
                            2
                     (d)  3, 3 , 3 , …, to n = 8                                          29 524
                                                                    geometric progression is 4  .  C2
                                                                                          59 049
                                   7
                   22.  It is given that   ,  –7,  14,  …  is  a  geometric
                                   2                             33.  Determine the value of n when the sum of the  CHAP
                     progression. Find the sum from 3rd term to 8th   first n of the geometric progression 125, –25,   5
                     term of the geometric progression.  C2                  104
                                                                    5, … is 104  .  C2
                                                                             625
                   23.  Find the sum from 4th term to 9th term of the
                     geometric progression 4, –6, 9, …  C2       34.  It is given that the 2nd term and the 5th
                                                                    term  of  a  geometric  progression  are  –27  and
                   24.  It  is  given  that  9,  –18,  36,  …  is  a  geometric   1 respectively. Find   C3
                     progression. Find the sum from 6th term to
                     18th term of the geometric progression.  C2    (a)  the first term and the common ratio,
                                                                    (b)  the sum of the first 13 terms,
                   25.  It is given that the nth term of a geometric   of the geometric progression.
                                       5
                     progression is T  = –  (–2) . Find  C2
                                           n
                                  n                              35.  Given that the 4th term and the 10th term
                                       2
                                                                                                         1
                     (a)  the first term and the common ratio,      of  a  geometric  progression  are  –16  and  –
                     (b)  the sum of the first 6 terms,             respectively. Find   C3              4
                     of the geometric progression.
                                                                    (a)  the first term and the common ratio,
                   26.  Given that the  nth term of a geometric     (b)  the sum  from the 5th term  to the 12th
                     progression  is  T   =  3 3  –  n ,  find  the  sum  of  the   term,
                                   n
                     first 10 terms.  C2                            of the geometric progression.
                   27.  It is given that the  nth term of a geometric     36.  In a geometric progression, the 3rd term and
                                       625                          the sum of 4th and 5th term are 60 and 360
                     progression is  T   =   . Find the sum from
                                   n    n                           respectively. Find   C3
                                       5
                     the 5th term to the 12th term of the geometric   (a)  the first term and the common ratio,
                     progression.  C2
                                                                    (b)  the sum of the first 11 terms,
                                                                    of the geometric progression.
                   28.  The sum of the first nth terms of a geometric
                                             2 2n + 1  – 2
                     progression is given by S  =    . Find      37.  Find  the  sum  to  infinity  of  the  following
                                          n
                                                3        C2         geometry progression.  C2
                     (a)  the sum of the first 7 terms,

                                                                                 1
                     (b)  the 8th term,                             (a)  120, 80, 53 , …
                     of the geometric progression.                               3
                                                                           2   7
                                                                    (b)  8, 2 , 1 , …
                   29.  Given that the sum of the first nth terms of a     3   9
                     geometric progression is given by S  = 4(2 n – 1 ).   (c)   1  ,   1 1  ,   1 1  2 , …
                                                                               
                                                   n
                     Find  C2                                           5  5 2   5 2
                     (a)  the sum from the 3rd to 7th term,         (d)  3x, 1,   1  , …
                     (b)  the nth term of the geometric progression          3x
                         in terms of n.                                 (in terms of x)
                                                                                                       99
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