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វិទយល័យសេម�ចឳ េខត�េស ម�ប                       35


                                       [ដំេ�ះ��យ]

        I. គណនាលីមីត៖
                     2
                  3
                 x – x + x – 1
                                            0
           ក. lim              (មានរាងមិនកំណត់ )
             x→1     x – 1                  0
                          2
                                                2
                   (x – 1)x + (x – 1)    (x – 1)(x + 1)
                                                                      2
                                                             2
             = lim                 = lim              = lim(x + 1) = 1 + 1 = 2
               x→1      (x – 1)      x→1    (x – 1)     x→1
                  3
                      2
                 x – x + x – 1
              lim             = 2
             x→1     x – 1
                    2
                  sin x – 1
                                         0
          ខ. lim           (មានរាងមិនកំណត់ )
             x→– 1 + sin x               0
                π
                2
                            ) (
                    ( sin x – 1 sin x + 1 )               (   )
                                             (
                                                    )
             = lim                    = lim sin x – 1 = sin – π  – 1 = –1 – 1 = –2
               x→–  π    sin x + 1      x→–  π              2
                   2                        2
                     2
                   sin x – 1
               lim         = –2
              x→– 1 + sin x
                 π
                 2
                  ( √        )
                      2
           គ. lim    x + x – x  (មានរាងមិនកំណត់+∞ – ∞)
             x→+∞
                     (          ) (         )
                      √           √
                         2
                                    2
                        x + x – x  x + x + x          x + x – x 2
                                                       2
             = lim         (          )       = lim    √
               x→+∞         √  2                x→+∞        1
                             x + x + x               x 1 +   + x
                                                            x
                           x                   1         1     1
             = lim    ( √        ) = lim   √         =       =
               x→+∞          1       x→+∞       1       1 + 1  2
                     x   1 +  + 1           1 +  + 1
                             x                  x
                              )
                   ( √            1
                       2
               lim    x + x – x =
              x→+∞                2
                 (  –x  x  )  2
                 e  + e  sin x
                                              0
          ឃ. lim                (មានរាងមិនកំណត់ )
             x→0      2x 2                    0
                                     0
                              2
                                                                       2
                   e –x  + e x  sin x  e + e 0  2           ( e –x  + e x )  sin x
             = lim         ·     =        × 1 =   = 1   lim               = 1
               x→0    2      x 2      2         2       x→0      2x 2
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