Page 67 - Calculus Demystified
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                                        (a)  θ = π/24                       CHAPTER 1         Basics
                                        (b)  θ =−π/3
                                        (c)  θ = 27π/12
                                        (d)  θ = 9π/16
                                        (e)  θ = 3
                                        (f)  θ =−5
                                 16. Convert each of the following angles from degree measure to radian
                                      measure.
                                        (a)  θ = 65 ◦
                                        (b)  θ = 10 ◦
                                        (c)  θ =−75  ◦
                                        (d)  θ =−120  ◦
                                        (e)  θ = π  ◦
                                        (f)  θ = 3.14 ◦
                                 17. For each of the following pairs of functions, calculate f ◦ g and g ◦ f .

                                                     2
                                        (a)  f(x) = x + 2x + 3      g(x) = (x − 1) 2
                                                    √                      √
                                                                            3
                                                                              2
                                        (b)  f(x) =   x + 1         g(x) =   x − 2
                                                             2
                                                                                2
                                        (c)  f(x) = sin(x + 3x )    g(x) = cos(x − x)
                                        (d)  f(x) = e x+2           g(x) = ln(x − 5)
                                                                               2
                                                        2
                                        (e)  f(x) = sin(x + x)      g(x) = ln(x − x)
                                        (f)  f(x) = e x 2           g(x) = e −x 2
                                        (g)  f(x) = x(x + 1)(x + 2)  g(x) = (2x − 3)(x + 4)
                                 18. Consider each of the following as functions from R to R and say whether
                                      the function is invertible. If it is, find the inverse with an explicit formula.
                                                     3
                                        (a)  f(x) = x + 5
                                                     2
                                        (b)  g(x) = x − x
                                                           √
                                        (c)  h(x) = (sgn x) ·  |x|, where sgn x is +1if x is positive, −1if x is
                                             negative, 0 if x is 0.
                                                     5
                                        (d)  f(x) = x + 8
                                        (e)  g(x) = e −3x
                                        (f)  h(x) = sin x
                                        (g)  f(x) = tan x
                                                             2
                                        (h)  g(x) = (sgn x) · x , where sgn x is +1if x is positive, −1if x is
                                             negative, 0 if x is 0.
                                 19. For each of the functions in Exercise 18, graph both the function and its
                                      inverse in the same set of axes.
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