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)set output tex off

)set output algebra on

integrate(sqrt(a*t^2+b*t+c),t)

   (1)
   [
                                                    +--------------+
                           3          2     2   +-+ |   2
             ((16a b c - 4b )t + 32a c  - 8b c)\|c \|a t  + b t + c
           +
                   2 2    4  2             2     3           3     2 2
             (- 16a c  + b )t  + (- 32a b c  + 8b c)t - 32a c  + 8b c
        *
           log
                                     +--------------+
                     +-+ +-+         |   2                   +-+
                  (2\|a \|c  - 2a t)\|a t  + b t + c  + 2a t\|c
                +
                         2             +-+
                  (- 2a t  - b t - 2c)\|a
             /
                      +--------------+
                  +-+ |   2
                2\|c \|a t  + b t + c  - b t - 2c
       +
                  2        2  3                  3  2           2     2     +-+
           ((- 16a c - 4a b )t  + (- 40a b c - 2b )t  + (- 32a c  - 8b c)t)\|a
        *
            +--------------+
            |   2
           \|a t  + b t + c
       +
                  2   4       2         2  3                3  2
               16a b t  + (32a c + 24a b )t  + (56a b c + 6b )t
             +
                     2     2
               (32a c  + 8b c)t
        *
            +-+ +-+
           \|a \|c
    /
                                   +--------------+
                           +-+ +-+ |   2
         (32a b t + 64a c)\|a \|c \|a t  + b t + c
       +
                2        2  2                    2  +-+
         ((- 32a c - 8a b )t  - 64a b c t - 64a c )\|a
     ,

                                                    +--------------+
                           3          2     2   +-+ |   2
             ((16a b c - 4b )t + 32a c  - 8b c)\|c \|a t  + b t + c
           +
                   2 2    4  2             2     3           3     2 2
             (- 16a c  + b )t  + (- 32a b c  + 8b c)t - 32a c  + 8b c
        *
                       +--------------+
                 +---+ |   2               +---+ +-+
                \|- a \|a t  + b t + c  - \|- a \|c
           atan(------------------------------------)
                                 a t
       +
                 2        2  3                 3  2           2     2     +---+
           ((- 8a c - 2a b )t  + (- 20a b c - b )t  + (- 16a c  - 4b c)t)\|- a
        *
            +--------------+
            |   2
           \|a t  + b t + c
       +
              2   4       2         2  3                3  2         2     2
           (8a b t  + (16a c + 12a b )t  + (28a b c + 3b )t  + (16a c  + 4b c)t)
        *
            +---+ +-+
           \|- a \|c
    /
                                     +--------------+
                           +---+ +-+ |   2
         (16a b t + 32a c)\|- a \|c \|a t  + b t + c
       +
                2        2  2                    2  +---+
         ((- 16a c - 4a b )t  - 32a b c t - 32a c )\|- a
     ]

Output from Maxima is also weird. Maxima output parse error!