Page 316 - Calculus Demystified
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Chapter 7
                                          1         2x + 1                                       303
                              (c)                  ·
                                           2
                                                      2
                                   1 +[ln(x + x)] 2  x + x
                                           1
                                                         2
                              (d)                     · sec x
                                                2
                                   | tan x| [tan x] − 1
                       10.    (a)  Tan −1 2
                                        x + C
                              (b)  Sin −1 3
                                        x + C
                                   	           
 π/2                    π
                                            2
                              (c)   Sin −1 (sin x)  = Sin −1 1 − Sin −1 0 =  .
                                                0                       2
                                                                    √
                                   1        dx          1             2x
                              (d)           √       = √     · Tan −1  √    + C
                                   5   1 +[ 2/5x]  2     10            5
                     Chapter 7
                        1. We do (a), (b), (c), (d).
                                             2
                              (a)  Let u = log x and dv = 1 dx. Then
                                                                                1
                                                2          2
                                             log xdx = log x · x −   x · 2 log x ·  dx
                                                                                x

                                                            2
                                                      = x log x − 2   log xdx.
                                   Now let u = log x and dv = 1 dx. Then
                                                                                 1
                                             2            2
                                           log xdx = x log x − 2 log x · x −  x ·  dx
                                                                                 x
                                                          2
                                                   = x log x − 2x log x + 2x + C.
                              (b)  Let u = x and dv = e 3x  dx. Then
                                                                3x       3x
                                                     3         e        e
                                                 x · e xdx = x ·   −       · 1 dx
                                                                3        3
                                                               e 3x  e 3x
                                                          = x ·    −     + C.
                                                                3     9
                                           2
                              (c)  Let u = x and dv = cos xdx. Then

                                               2            2
                                              x cos xdx = x · sin x −   sin x · 2xdx.
                                   Now let u = 2x and dv = sin xdx. Then

                                      2            2
                                     x cos xdx = x · sin x − 2x · (− cos x) −  (− cos x) · 2 dx
                                                   2
                                               = x sin x + 2x cos x − 2 sin x + C.
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