Page 135 - Mathematics_Form_Two
P. 135

Logarithms



                (d)  log 2  8                          6.  Given that log2x = u and log2y = v,
                                                          write:
                                 3
                (b)  log 5 (5 125  )                     (a)  2 2u− 2  in terms of x
                         1000
                 (e)  log 1000                            (b)  2 4v+ 1  in terms of y
                       3
                (c)   log 0.0001                       7.  Find the value of  x in each of the
                        3
          FOR ONLINE READING ONLY
                 (f)   log0.001 5                         following equations:
                                                          (a) log x = log 5 2log 3+  a
                                                                 a
                                                                         a
            3.  Simplify  each  of the  following
               expressions using the laws of              (b) log x = 3log 15 2log 15−  a            Mathematics for Secondary Schools
                                                                 a
                                                                           a
               logarithms:                                (c)  log x =  log 4 log 5+  3
                                                                 3
                                                                         3
                    log64
                (a)                                       (d)  log x = log 2 +  log5
                     log 4                                (e)  log x =  log20 log200 log50−  +
                (b)  log 28 log 7−  2
                       2
                                                          (f) log x =  log2 log20 log5−  +
                (c)   log 10 log 8.1+  3
                       3
                                                       8.  Given that log 2 = 0.30103,
                (d)  log 20 log50+                        log 3 = 0.47712, and log 5 = 0.69897.

                         4
                (e) log3 +  log     10  81           Find the value of:
                                                         (a)  log 90
                        3
                (f)  log 4                                      1      6   5
                    log 4                                 (b)    log       
                                                                5      5  

            4.  Without using a calculator, find the   9.   If log y +  2log x =  3, express y in
               value of 2log5 + log36 – log9.              terms of x.

            5.  Use logarithmic laws to expand each   10.  Express p in terms of q for each of
               of the following expressions.              the following:
                                                                              
                         ⎛   x y  x y  − −3 3 ⎞    u 2  v          ( x +  ) y  2 2
                           2 2
                               ⎟
                               ⎟
                     log
                (a) log ⎜ ⎜ ⎜  25 ⎟   (b) log     zv 5     (a) log q −  (c) log  4log p =      
                        5 
                               ⎟
                        5⎜
                           25 ⎠  ⎝                    (b) log q +  log m =    z  log(m bp−    )
    x y   2  − 3        u 2  v              ( x +  ) y  2  
 (a) log 5     (b) log    5       (c) log       11.  Solve for x given
                                                       
    25                    zv                 z      log(x −  2) log(x−  −  1) 0=  .
   x y   2  − 3    u 2  v     ( x +  ) y  2      12. Evaluate each of the following
 (a) log 5     (b) log   5     (c) log             (a)  log9(81)       (c)  log2(16)
   25        zv        z    
                                                          (b)   log 36        (d)  log8(64)
                                                                   6

                                                   129
           Student's Book Form Two


                                                                                          11/10/2024   20:13:01
     MATHEMATIC F2 v5.indd   129
     MATHEMATIC F2 v5.indd   129                                                          11/10/2024   20:13:01
   130   131   132   133   134   135   136   137   138   139   140