|
2 | 2 |
|
3 | 3 | ## (一) 含有 $ax+b$ 的积分 |
4 | 4 |
|
5 | | -01. $\int \frac{\mathrm{d} x}{ax+b} = \frac{1}{a} \ln |ax+b| + C$ |
| 5 | +1. $\int \frac{\mathrm{d} x}{ax+b} = \frac{1}{a} \ln |ax+b| + C$ |
6 | 6 |
|
7 | | -02. $\int (ax+b)^{\mu} \mathrm{d} x = \frac{1}{a(\mu+1)} (ax+b)^{\mu+1} + C \quad (\mu \neq -1)$ |
| 7 | +2. $\int (ax+b)^{\mu} \mathrm{d} x = \frac{1}{a(\mu+1)} (ax+b)^{\mu+1} + C \quad (\mu \neq -1)$ |
8 | 8 |
|
9 | | -03. $\int \frac{x}{ax+b} \mathrm{d} x = \frac{1}{a^2} \left(ax + b - b \ln |ax+b| \right) + C$ |
| 9 | +3. $\int \frac{x}{ax+b} \mathrm{d} x = \frac{1}{a^2} \left(ax + b - b \ln |ax+b| \right) + C$ |
10 | 10 |
|
11 | | -04. $\int \frac{x^2}{ax+b} \mathrm{d} x = \frac{1}{a^3} \left[ \frac{1}{2} (ax+b)^2 - 2b (ax+b) + b^2 \ln |ax+b| \right] + C$ |
| 11 | +4. $\int \frac{x^2}{ax+b} \mathrm{d} x = \frac{1}{a^3} \left[ \frac{1}{2} (ax+b)^2 - 2b (ax+b) + b^2 \ln |ax+b| \right] + C$ |
12 | 12 |
|
13 | | -05. $\int \frac{\mathrm{d} x}{x(ax+b)} = -\frac{1}{b} \ln \left| \frac{ax+b}{x} \right| + C$ |
| 13 | +5. $\int \frac{\mathrm{d} x}{x(ax+b)} = -\frac{1}{b} \ln \left| \frac{ax+b}{x} \right| + C$ |
14 | 14 |
|
15 | | -06. $\int \frac{\mathrm{d} x}{x^2(ax+b)} = -\frac{1}{bx} + \frac{a}{b^2} \ln \left| \frac{ax+b}{x} \right| + C$ |
| 15 | +6. $\int \frac{\mathrm{d} x}{x^2(ax+b)} = -\frac{1}{bx} + \frac{a}{b^2} \ln \left| \frac{ax+b}{x} \right| + C$ |
16 | 16 |
|
17 | | -07. $\int \frac{x}{(ax+b)^2} \mathrm{d} x = \frac{1}{a^2} \left( \ln |ax+b| + \frac{b}{ax+b} \right) + C$ |
| 17 | +7. $\int \frac{x}{(ax+b)^2} \mathrm{d} x = \frac{1}{a^2} \left( \ln |ax+b| + \frac{b}{ax+b} \right) + C$ |
18 | 18 |
|
19 | | -08. $\int \frac{x^2}{(ax+b)^2} \mathrm{d} x = \frac{1}{a^3} \left(ax + b - 2b \ln |ax+b| - \frac{b^2}{ax+b} \right) + C$ |
| 19 | +8. $\int \frac{x^2}{(ax+b)^2} \mathrm{d} x = \frac{1}{a^3} \left(ax + b - 2b \ln |ax+b| - \frac{b^2}{ax+b} \right) + C$ |
20 | 20 |
|
21 | | -09. $\int \frac{\mathrm{d} x}{x(ax+b)^2} = \frac{1}{b(ax+b)} - \frac{1}{b^2} \ln \left| \frac{ax+b}{x} \right| + C$ |
| 21 | +9. $\int \frac{\mathrm{d} x}{x(ax+b)^2} = \frac{1}{b(ax+b)} - \frac{1}{b^2} \ln \left| \frac{ax+b}{x} \right| + C$ |
22 | 22 |
|
23 | 23 | ## (二) 含有 $\sqrt{ax+b}$ 的积分 |
24 | 24 |
|
|
42 | 42 | 17. $\int \frac{\sqrt{ax+b}}{x} \, \mathrm{d} x = 2 \sqrt{ax+b} + b \int \frac{\mathrm{d} x}{x \sqrt{ax+b}}$ |
43 | 43 |
|
44 | 44 | 18. $\int \frac{\sqrt{ax+b}}{x^2} \, \mathrm{d} x = -\frac{\sqrt{ax+b}}{x} + \frac{a}{2} \int \frac{\mathrm{d} x}{x \sqrt{ax+b}}$ |
| 45 | + |
| 46 | +## (三) 含有 $x^2 \pm a^2$ 的积分 |
| 47 | + |
| 48 | +19. $\int \frac{\mathrm{d} x}{x^2 + a^2} = \frac{1}{a} \arctan \frac{x}{a} + C$ |
| 49 | + |
| 50 | +20. $\int \frac{\mathrm{d} x}{(x^2 + a^2)^n} = \frac{x}{2(n-1)a^2(x^2 + a^2)^{n-1}} + \frac{2n-3}{2(n-1)a^2} \int \frac{\mathrm{d} x}{(x^2 + a^2)^{n-1}}$ |
| 51 | + |
| 52 | +21. $\int \frac{\mathrm{d} x}{x^2 - a^2} = \frac{1}{2a} \ln \left| \frac{x-a}{x+a} \right| + C$ |
| 53 | + |
| 54 | +## (四) 含有 $ax^2 + b \quad (a > 0)$ 的积分 |
| 55 | + |
| 56 | +22. $\int \frac{\mathrm{d} x}{ax^2 + b} = \begin{cases} |
| 57 | + \frac{1}{\sqrt{ab}} \arctan \sqrt{\frac{a}{b}} x + C & (b > 0) \\ |
| 58 | + \frac{1}{2 \sqrt{-ab}} \ln \left| \frac{\sqrt{a} x - \sqrt{-b}}{\sqrt{a} x + \sqrt{-b}} \right| + C & (b < 0) |
| 59 | + \end{cases}$ |
| 60 | + |
| 61 | +23. $\int \frac{x}{ax^2 + b} \mathrm{d} x = \frac{1}{2a} \ln \left| ax^2 + b \right| + C$ |
| 62 | + |
| 63 | +24. $\int \frac{x^2}{ax^2 + b} \mathrm{d} x = \frac{x}{a} - \frac{b}{a} \int \frac{\mathrm{d} x}{ax^2 + b}$ |
| 64 | + |
| 65 | +25. $\int \frac{\mathrm{d} x}{x(ax^2 + b)} = \frac{1}{2b} \ln \frac{x^2}{| ax^2 + b |} + C$ |
| 66 | + |
| 67 | +26. $\int \frac{\mathrm{d} x}{x^2 (ax^2 + b)} = -\frac{1}{bx} - \frac{a}{b} \int \frac{\mathrm{d} x}{ax^2 + b}$ |
| 68 | + |
| 69 | +27. $\int \frac{\mathrm{d} x}{x^3 (ax^2 + b)} = \frac{a}{2b^2} \ln \frac{| ax^2 + b |}{x^2} - \frac{1}{2bx^2} + C$ |
| 70 | + |
| 71 | +28. $\int \frac{\mathrm{d} x}{(ax^2 + b)^2} = \frac{x}{2b(ax^2 + b)} + \frac{1}{2b} \int \frac{\mathrm{d} x}{ax^2 + b}$ |
| 72 | + |
| 73 | +## (五) 含有 $ax^2 + bx + c \quad (a > 0)$ 的积分 |
| 74 | + |
| 75 | +29. $\int \frac{\mathrm{d} x}{ax^2 + bx + c} = \begin{cases} |
| 76 | + \frac{2}{\sqrt{4ac - b^2}} \arctan \left( \frac{2ax + b}{\sqrt{4ac - b^2}} \right) + C & (b^2 < 4ac) \\ |
| 77 | + \frac{1}{\sqrt{b^2 - 4ac}} \ln \left| \frac{2ax + b - \sqrt{b^2 - 4ac}}{2ax + b + \sqrt{b^2 - 4ac}} \right| + C & (b^2 > 4ac) |
| 78 | + \end{cases}$ |
| 79 | + |
| 80 | +30. $\int \frac{x}{ax^2 + bx + c} \mathrm{d} x = \frac{1}{2a} \ln \left| ax^2 + bx + c \right| - \frac{b}{2a} \int \frac{\mathrm{d} x}{ax^2 + bx + c}$ |
| 81 | + |
| 82 | +## (六) 含有 $\sqrt{x^2+a^2} \quad (a>0)$ 的积分 |
| 83 | + |
| 84 | +31. $\int \frac{\mathrm{d} x}{\sqrt{x^2+a^2}} = \text{arsh} \frac{x}{a} + C_1 = \ln(x + \sqrt{x^2 + a^2}) + C$ |
| 85 | + |
| 86 | +32. $\int \frac{\mathrm{d} x}{\sqrt{(x^2+a^2)^3}} = \frac{x}{a^2 \sqrt{x^2 + a^2}} + C$ |
| 87 | + |
| 88 | +33. $\int \frac{x}{\sqrt{x^2 + a^2}} \, \mathrm{d} x = \sqrt{x^2 + a^2} + C$ |
| 89 | + |
| 90 | +34. $\int \frac{x}{\sqrt{(x^2 + a^2)^3}} \mathrm{d} x = -\frac{1}{\sqrt{x^2 + a^2}} + C$ |
| 91 | + |
| 92 | +35. $\int \frac{x^2}{\sqrt{x^2 + a^2}} \, \mathrm{d} x = \frac{x}{2} \sqrt{x^2 + a^2} - \frac{a^2}{2} \ln(x + \sqrt{x^2 + a^2}) + C$ |
| 93 | + |
| 94 | +36. $\int \frac{x^2}{\sqrt{(x^2 + a^2)^3}} \, \mathrm{d} x = -\frac{x}{\sqrt{x^2 + a^2}} + \ln(x + \sqrt{x^2 + a^2}) + C$ |
| 95 | + |
| 96 | +37. $\int \frac{\mathrm{d} x}{x \sqrt{x^2 + a^2}} = \frac{1}{a} \ln \frac{\sqrt{x^2 + a^2} - a}{|x|} + C$ |
| 97 | + |
| 98 | +38. $\int \frac{\mathrm{d} x}{x^2 \sqrt{x^2 + a^2}} = -\frac{\sqrt{x^2 + a^2}}{a^2 x} + C$ |
| 99 | + |
| 100 | +39. $\int \sqrt{x^2 + a^2} \, \mathrm{d} x = \frac{x}{2} \sqrt{x^2 + a^2} + \frac{a^2}{2} \ln(x + \sqrt{x^2 + a^2}) + C$ |
| 101 | + |
| 102 | +40. $\int \sqrt{(x^2 + a^2)^3} \, \mathrm{d} x = \frac{x}{8} (2x^2 + 5a^2) \sqrt{x^2 + a^2} + \frac{3}{8} a^4 \ln(x + \sqrt{x^2 + a^2}) + C$ |
| 103 | + |
| 104 | +41. $\int x \sqrt{x^2 + a^2} \, \mathrm{d} x = \frac{1}{3} \sqrt{(x^2 + a^2)^3} + C$ |
| 105 | + |
| 106 | +42. $\int x^2 \sqrt{x^2 + a^2} \, \mathrm{d} x = \frac{x}{8} (2x^2 + a^2) \sqrt{x^2 + a^2} - \frac{a^4}{8} \ln(x + \sqrt{x^2 + a^2}) + C$ |
| 107 | + |
| 108 | +43. $\int \frac{\sqrt{x^2 + a^2}}{x} \, \mathrm{d} x = \sqrt{x^2 + a^2} + a \ln \frac{\sqrt{x^2 + a^2} - a}{|x|} + C$ |
| 109 | + |
| 110 | +44. $\int \frac{\sqrt{x^2 + a^2}}{x^2} \, \mathrm{d} x = -\frac{\sqrt{x^2 + a^2}}{x} + \ln(x + \sqrt{x^2 + a^2}) + C$ |
| 111 | + |
| 112 | +## (七) 含有 $\sqrt{x^2 - a^2} \quad (a > 0)$ 的积分 |
| 113 | + |
| 114 | +45. $\int \frac{\mathrm{d} x}{\sqrt{x^2 - a^2}} = \frac{x}{|x|} \text{arch} \frac{|x|}{a} + C_1 = \ln \left| x + \sqrt{x^2 - a^2} \right| + C$ |
| 115 | + |
| 116 | +46. $\int \frac{\mathrm{d} x}{\left( \sqrt{x^2 - a^2} \right)^3} = - \frac{x}{a^2 \sqrt{x^2 - a^2}} + C$ |
| 117 | + |
| 118 | +47. $\int \frac{x}{\sqrt{x^2 - a^2}} \mathrm{d} x = \sqrt{x^2 - a^2} + C$ |
| 119 | + |
| 120 | +48. $\int \frac{x}{\sqrt{(x^2 - a^2)^3}} \mathrm{d} x = - \frac{1}{\sqrt{x^2 - a^2}} + C$ |
| 121 | + |
| 122 | +49. $\int \frac{x^2}{\sqrt{x^2 - a^2}} \mathrm{d} x = \frac{x}{2} \sqrt{x^2 - a^2} + \frac{a^2}{2} \ln \left| x + \sqrt{x^2 - a^2} \right| + C$ |
| 123 | + |
| 124 | +50. $\int \frac{x^2}{\left( \sqrt{x^2 - a^2} \right)^3} \mathrm{d} x = - \frac{x}{\sqrt{x^2 - a^2}} + \ln \left| x + \sqrt{x^2 - a^2} \right| + C$ |
| 125 | + |
| 126 | +51. $\int \frac{\mathrm{d} x}{x \sqrt{x^2 - a^2}} = \frac{1}{a} \text{arccos} \frac{a}{|x|} + C$ |
| 127 | + |
| 128 | +52. $\int \frac{\mathrm{d} x}{x^2 \sqrt{x^2 - a^2}} = \frac{\sqrt{x^2 - a^2}}{a^2 x} + C$ |
| 129 | + |
| 130 | +53. $\int \sqrt{x^2 - a^2} \mathrm{d} x = \frac{x}{2} \sqrt{x^2 - a^2} - \frac{a^2}{2} \ln \left| x + \sqrt{x^2 - a^2} \right| + C$ |
| 131 | + |
| 132 | +54. $\int \sqrt{(x^2 - a^2)^3} \, \mathrm{d} x = \frac{x}{8} \left(2x^2 - 5a^2\right) \sqrt{x^2 - a^2} + \frac{3}{8} a^4 \ln \left| x + \sqrt{x^2 - a^2} \right| + C$ |
| 133 | + |
| 134 | +55. $\int x \sqrt{x^2 - a^2} \, \mathrm{d} x = \frac{1}{3} \sqrt{(x^2 - a^2)^3} + C$ |
| 135 | + |
| 136 | +56. $\int x^2 \sqrt{x^2 - a^2} \, \mathrm{d} x = \frac{x}{8} \left(2x^2 - a^2\right) \sqrt{x^2 - a^2} - \frac{a^4}{8} \ln \left| x + \sqrt{x^2 - a^2} \right| + C$ |
| 137 | + |
| 138 | +57. $\int \frac{\sqrt{x^2 - a^2}}{x} \, \mathrm{d} x = \sqrt{x^2 - a^2} - a \arccos \frac{a}{|x|} + C$ |
| 139 | + |
| 140 | +58. $\int \frac{\sqrt{x^2 - a^2}}{x^2} \, \mathrm{d} x = -\frac{\sqrt{x^2 - a^2}}{x} + \ln \left| x + \sqrt{x^2 - a^2} \right| + C$ |
| 141 | + |
| 142 | +## (八) 含有 $\sqrt{a^2 - x^2} \quad (a > 0)$ 的积分 |
| 143 | + |
| 144 | +59. $\int \frac{\mathrm{d} x}{\sqrt{a^2 - x^2}} = \arcsin \frac{x}{a} + C$ |
| 145 | + |
| 146 | +60. $\int \frac{\mathrm{d} x}{\left( \sqrt{a^2 - x^2} \right)^3} = \frac{x}{a^2 \sqrt{a^2 - x^2}} + C$ |
| 147 | + |
| 148 | +61. $\int \frac{x}{\sqrt{a^2 - x^2}} \mathrm{d} x = -\sqrt{a^2 - x^2} + C$ |
| 149 | + |
| 150 | +62. $\int \frac{x}{\sqrt{(a^2 - x^2)^3}} \mathrm{d} x = \frac{1}{\sqrt{a^2 - x^2}} + C$ |
| 151 | + |
| 152 | +63. $\int \frac{x^2}{\sqrt{a^2 - x^2}} \mathrm{d} x = -\frac{x}{2} \sqrt{a^2 - x^2} + \frac{a^2}{2} \arcsin \frac{x}{a} + C$ |
| 153 | + |
| 154 | +64. $\int \frac{x^2}{\sqrt{(a^2 - x^2)^3}} \mathrm{d} x = \frac{x}{\sqrt{a^2 - x^2}} - \arcsin \frac{x}{a} + C$ |
| 155 | + |
| 156 | +65. $\int \frac{\mathrm{d} x}{x \sqrt{a^2 - x^2}} = \frac{1}{a} \ln \frac{a - \sqrt{a^2 - x^2}}{|x|} + C$ |
| 157 | + |
| 158 | +66. $\int \frac{\mathrm{d} x}{x^2 \sqrt{a^2 - x^2}} = -\frac{\sqrt{a^2 - x^2}}{a^2 x} + C$ |
| 159 | + |
| 160 | +67. $\int \sqrt{a^2 - x^2} \mathrm{d} x = \frac{x}{2} \sqrt{a^2 - x^2} + \frac{a^2}{2} \arcsin \frac{x}{a} + C$ |
| 161 | + |
| 162 | +68. $\int \sqrt{\left( a^2 - x^2 \right)^3} \mathrm{d} x = \frac{x}{8} \left( 5a^2 - 2x^2 \right) \sqrt{a^2 - x^2} + \frac{3}{8} a^4 \arcsin \frac{x}{a} + C$ |
| 163 | + |
| 164 | +69. $\int x \sqrt{a^2 - x^2} \mathrm{d} x = -\frac{1}{3} \sqrt{\left( a^2 - x^2 \right)^3} + C$ |
| 165 | + |
| 166 | +70. $\int x^2 \sqrt{a^2 - x^2} \mathrm{d} x = \frac{x}{8} (2x^2 - a^2) \sqrt{a^2 - x^2} + \frac{a^4}{8} \arcsin \frac{x}{a} + C$ |
| 167 | + |
| 168 | +71. $\int \frac{\sqrt{a^2 - x^2}}{x} \mathrm{d} x = \sqrt{a^2 - x^2} + a \ln \frac{a - \sqrt{a^2 - x^2}}{|x|} + C$ |
| 169 | + |
| 170 | +72. $\int \frac{\sqrt{a^2 - x^2}}{x^2} \mathrm{d} x = - \frac{\sqrt{a^2 - x^2}}{x} - \arcsin \frac{x}{a} + C$ |
| 171 | + |
| 172 | +## (九) 含有 $\sqrt{\pm ax^2 + bx + c} \quad (a > 0)$ 的积分 |
| 173 | + |
| 174 | +73. $\int \frac{\mathrm{d} x}{\sqrt{ax^2 + bx + c}} = \frac{1}{\sqrt{a}} \ln \left| 2ax + b + 2 \sqrt{a} \sqrt{ax^2 + bx + c} \right| + C$ |
| 175 | + |
| 176 | +74. $\int \sqrt{ax^2 + bx + c} \mathrm{d} x = \frac{2ax + b}{4a} \sqrt{ax^2 + bx + c} + \frac{4ac - b^2}{8 \sqrt{a^3}} \ln \left| 2ax + b + 2 \sqrt{a} \sqrt{ax^2 + bx + c} \right| + C$ |
| 177 | + |
| 178 | +75. $\int \frac{x}{\sqrt{ax^2 + bx + c}} \mathrm{d} x = \frac{1}{a} \sqrt{ax^2 + bx + c} - \frac{b}{2 \sqrt{a^3}} \ln \left| 2ax + b + 2 \sqrt{a} \sqrt{ax^2 + bx + c} \right| + C$ |
| 179 | + |
| 180 | +76. $\int \frac{\mathrm{d} x}{\sqrt{c + bx - ax^2}} = \frac{1}{\sqrt{a}} \arcsin \frac{2ax - b}{\sqrt{b^2 + 4ac}} + C$ |
| 181 | + |
| 182 | +77. $\int \sqrt{c + bx - ax^2} \mathrm{d} x = \frac{2ax - b}{4a} \sqrt{c + bx - ax^2} + \frac{b^2 + 4ac}{8 \sqrt{a^3}} \arcsin \frac{2ax - b}{\sqrt{b^2 + 4ac}} + C$ |
| 183 | + |
| 184 | +78. $\int \frac{x}{\sqrt{c + bx - ax^2}} \mathrm{d} x = - \frac{1}{a} \sqrt{c + bx - ax^2} + \frac{b}{2 \sqrt{a^3}} \arcsin \frac{2ax - b}{\sqrt{b^2 + 4ac}} + C$ |
| 185 | + |
| 186 | +## (十) 含有 $\sqrt{\pm \frac{x-a}{x-b}}$ 或 $\sqrt{(x-a)(b-x)}$ 的积分 |
| 187 | + |
| 188 | +79. $\int \sqrt{\frac{x-a}{x-b}} \, \mathrm{d} x = (x-b) \sqrt{\frac{x-a}{x-b}} + (b-a) \ln \left( \sqrt{|x-a|} + \sqrt{|x-b|} \right) + C$ |
| 189 | + |
| 190 | +80. $\int \sqrt{\frac{x-a}{b-x}} \, \mathrm{d} x = (x-b) \sqrt{\frac{x-a}{b-x}} + (b-a) \arcsin \sqrt{\frac{x-a}{b-a}} + C$ |
| 191 | + |
| 192 | +81. $\int \frac{\mathrm{d} x}{\sqrt{(x-a)(b-x)}} = 2 \arcsin \sqrt{\frac{x-a}{b-a}} + C \quad (a < b)$ |
| 193 | + |
| 194 | +82. $\int \sqrt{(x-a)(b-x)} \, \mathrm{d} x = \frac{2x-a-b}{4} \sqrt{(x-a)(b-x)} + \frac{(b-a)^2}{4} \arcsin \sqrt{\frac{x-a}{b-a}} + C \quad (a < b)$ |
| 195 | + |
| 196 | +## (十一) 含有三角函数的积分 |
| 197 | + |
| 198 | +83. $\int \sin x \, \mathrm{d} x = -\cos x + C$ |
| 199 | + |
| 200 | +84. $\int \cos x \, \mathrm{d} x = \sin x + C$ |
| 201 | + |
| 202 | +85. $\int \tan x \, \mathrm{d} x = -\ln | \cos x | + C$ |
| 203 | + |
| 204 | +86. $\int \cot x \, \mathrm{d} x = \ln | \sin x | + C$ |
| 205 | + |
| 206 | +87. $\int \sec x \, \mathrm{d} x = \ln \left| \tan \left( \frac{\pi}{4} + \frac{x}{2} \right) \right| + C = \ln | \sec x + \tan x | + C$ |
| 207 | + |
| 208 | +88. $\int \csc x \, \mathrm{d} x = \ln \left| \tan \frac{x}{2} \right| + C = \ln | \csc x - \cot x | + C$ |
| 209 | + |
| 210 | +89. $\int \sec^2 x \, \mathrm{d} x = \tan x + C$ |
| 211 | + |
| 212 | +90. $\int \csc^2 x \, \mathrm{d} x = -\cot x + C$ |
| 213 | + |
| 214 | +91. $\int \sec x \tan x \, \mathrm{d} x = \sec x + C$ |
| 215 | + |
| 216 | +92. $\int \csc x \cot x \, \mathrm{d} x = -\csc x + C$ |
| 217 | + |
| 218 | +93. $\int \sin^2 x \, \mathrm{d} x = \frac{x}{2} - \frac{1}{4} \sin 2x + C$ |
| 219 | + |
| 220 | +94. $\int \cos^2 x \, \mathrm{d} x = \frac{x}{2} + \frac{1}{4} \sin 2x + C$ |
| 221 | + |
| 222 | +95. $\int \sin^n x \, \mathrm{d} x = \frac{1}{n} \sin^{n-1} x \cos x + \frac{n-1}{n} \int \sin^{n-2} x \, \mathrm{d} x$ |
| 223 | + |
| 224 | +96. $\int \cos^n x \, \mathrm{d} x = \frac{1}{n} \cos^{n-1} x \sin x + \frac{n-1}{n} \int \cos^{n-2} x \, \mathrm{d} x$ |
| 225 | + |
| 226 | +97. $\int \frac{\mathrm{d} x}{\sin^n x} = -\frac{1}{n-1} \cdot \frac{\cos x}{\sin^{n-1} x} + \frac{n-2}{n-1} \int \frac{\mathrm{d} x}{\sin^{n-2} x}$ |
| 227 | + |
| 228 | +98. $\int \frac{\mathrm{d} x}{\cos^n x} = \frac{1}{n-1} \cdot \frac{\sin x}{\cos^{n-1} x} + \frac{n-2}{n-1} \int \frac{\mathrm{d} x}{\cos^{n-2} x}$ |
| 229 | + |
| 230 | +99. $\int \cos^m x \sin^n x \, \mathrm{d} x \\ |
| 231 | + = \frac{1}{m+n} \cos^{m-1} x \sin^{n+1} x + \frac{m-1}{m+n} \int \cos^{m-2} x \sin^n x \, \mathrm{d} x \\ |
| 232 | + = -\frac{1}{m+n} \cos^{m+1} x \sin^{n-1} x + \frac{n-1}{m+n} \int \cos^m x \sin^{n-2} x \, \mathrm{d} x$ |
| 233 | + |
| 234 | +100. $\int \sin ax \cos bx \, \mathrm{d} x = -\frac{1}{2(a+b)} \cos (a+b)x - \frac{1}{2(a-b)} \cos (a-b)x + C$ |
| 235 | + |
| 236 | +101. $\int \sin ax \sin bx \, \mathrm{d} x = -\frac{1}{2(a+b)} \sin (a+b)x + \frac{1}{2(a-b)} \sin (a-b)x + C$ |
| 237 | + |
| 238 | +102. $\int \cos ax \cos bx\mathrm{d} x = \frac{1}{2(a+b)}\sin (a+b)x + \frac{1}{2(a-b)}\sin (a-b)x + C$ |
| 239 | + |
| 240 | +103. $\int \frac{\mathrm{d} x}{a+b\sin x} = \frac{2}{\sqrt{a^2-b^2}} \arctan \frac{a \tan \frac{x}{2} + b}{\sqrt{a^2-b^2}} + C \quad (a^2 > b^2)$ |
| 241 | + |
| 242 | +104. $\int \frac{\mathrm{d} x}{a+b\sin x} = \frac{1}{\sqrt{b^2-a^2}} \ln \left| \frac{a \tan \frac{x}{2} + b - \sqrt{b^2-a^2}}{a \tan \frac{x}{2} + b + \sqrt{b^2-a^2}} \right| + C \quad (a^2 < b^2)$ |
| 243 | + |
| 244 | +105. $\int \frac{\mathrm{d} x}{a+b\cos x} = \frac{2}{a+b} \sqrt{\frac{a+b}{a-b}} \arctan \left( \sqrt{\frac{a-b}{a+b}} \tan \frac{x}{2} \right) + C \quad (a^2 > b^2)$ |
| 245 | + |
| 246 | +106. $\int \frac{\mathrm{d} x}{a+b\cos x} = \frac{1}{a+b} \sqrt{\frac{a+b}{b-a}} \ln \left| \frac{\tan \frac{x}{2} + \sqrt{\frac{a+b}{b-a}}}{\tan \frac{x}{2} - \sqrt{\frac{a+b}{b-a}}} \right| + C \quad (a^2 < b^2)$ |
| 247 | + |
| 248 | +107. $\int \frac{\mathrm{d} x}{a^2 \cos^2 x + b^2 \sin^2 x} = \frac{1}{ab} \arctan \left( \frac{b}{a} \tan x \right) + C$ |
| 249 | + |
| 250 | +108. $\int \frac{\mathrm{d} x}{a^2 \cos^2 x - b^2 \sin^2 x} = \frac{1}{2ab} \ln \left| \frac{b \tan x + a}{b \tan x - a} \right| + C$ |
| 251 | + |
| 252 | +109. $\int x \sin ax \mathrm{d} x = \frac{1}{a^2} \sin ax - \frac{1}{a} x \cos ax + C$ |
| 253 | + |
| 254 | +110. $\int x^2 \sin ax \mathrm{d} x = -\frac{1}{a} x^2 \cos ax + \frac{2}{a^2} x \sin ax + \frac{2}{a^3} \cos ax + C$ |
| 255 | + |
| 256 | +111. $\int x \cos ax \mathrm{d} x = \frac{1}{a^2} \cos ax + \frac{1}{a} x \sin ax + C$ |
| 257 | + |
| 258 | +112. $\int x^2 \cos ax \mathrm{d} x = \frac{1}{a} x^2 \sin ax + \frac{2}{a^2} x \cos ax - \frac{2}{a^3} \sin ax + C$ |
| 259 | + |
| 260 | +## (十二) 含有反三角函数的积分 (其中 $a > 0$) |
| 261 | + |
| 262 | +113. $\int \arcsin \frac{x}{a} \mathrm{d} x = x \arcsin \frac{x}{a} + \sqrt{a^2 - x^2} + C$ |
| 263 | + |
| 264 | +114. $\int x \arcsin \frac{x}{a} \mathrm{d} x = \left( \frac{x^2}{2} - \frac{a^2}{4} \right) \arcsin \frac{x}{a} + \frac{x}{4} \sqrt{a^2 - x^2} + C$ |
| 265 | + |
| 266 | +115. $\int x^2 \arcsin \frac{x}{a} \mathrm{d} x = \frac{x^3}{3} \arcsin \frac{x}{a} + \frac{1}{9} (x^2 + 2a^2) \sqrt{a^2 - x^2} + C$ |
| 267 | + |
| 268 | +116. $\int \arccos \frac{x}{a} \mathrm{d} x = x \arccos \frac{x}{a} - \sqrt{a^2 - x^2} + C$ |
| 269 | + |
| 270 | +117. $\int x \arccos \frac{x}{a} \,\mathrm{d} x = \left( \frac{x^2}{2} - \frac{a^2}{4} \right) \arccos \frac{x}{a} - \frac{x}{4} \sqrt{a^2 - x^2} + C$ |
| 271 | + |
| 272 | +118. $\int x^2 \arccos \frac{x}{a} \,\mathrm{d} x = \frac{x^3}{3} \arccos \frac{x}{a} - \frac{1}{9} (x^2 + 2a^2) \sqrt{a^2 - x^2} + C$ |
| 273 | + |
| 274 | +119. $\int \arctan \frac{x}{a} \,\mathrm{d} x = x \arctan \frac{x}{a} - \frac{a}{2} \ln \left( a^2 + x^2 \right) + C$ |
| 275 | + |
| 276 | +120. $\int x \arctan \frac{x}{a} \,\mathrm{d} x = \frac{1}{2} \left( a^2 + x^2 \right) \arctan \frac{x}{a} - \frac{a}{2} x + C$ |
| 277 | + |
| 278 | +121. $\int x^2 \arctan \frac{x}{a} \,\mathrm{d} x = \frac{x^3}{3} \arctan \frac{x}{a} - \frac{a}{6} x^2 + \frac{a^3}{6} \ln \left( a^2 + x^2 \right) + C$ |
| 279 | + |
| 280 | +## (十三) 含有指数函数的积分 |
| 281 | + |
| 282 | +122. $\int a^x \,\mathrm{d} x = \frac{1}{\ln a} a^x + C$ |
| 283 | + |
| 284 | +123. $\int e^{ax} \,\mathrm{d} x = \frac{1}{a} e^{ax} + C$ |
| 285 | + |
| 286 | +124. $\int x e^{ax} \,\mathrm{d} x = \frac{1}{a^2} (ax - 1) e^{ax} + C$ |
| 287 | + |
| 288 | +125. $\int x^n e^{ax} \,\mathrm{d} x = \frac{1}{a} x^n e^{ax} - \frac{n}{a} \int x^{n-1} e^{ax} \,\mathrm{d} x$ |
| 289 | + |
| 290 | +126. $\int x a^x \,\mathrm{d} x = \frac{x}{\ln a} a^x - \frac{1}{(\ln a)^2} a^x + C$ |
| 291 | + |
| 292 | +127. $\int x^n a^x \,\mathrm{d} x = \frac{1}{\ln a} x^n a^x - \frac{n}{\ln a} \int x^{n-1} a^x \,\mathrm{d} x$ |
| 293 | + |
| 294 | +128. $\int e^{ax} \sin bx \,\mathrm{d} x = \frac{1}{a^2 + b^2} e^{ax} (a \sin bx - b \cos bx) + C$ |
| 295 | + |
| 296 | +129. $\int e^{ax} \cos bx \,\mathrm{d} x = \frac{1}{a^2 + b^2} e^{ax} (b \sin bx + a \cos bx) + C$ |
| 297 | + |
| 298 | +130. $\int e^{ax} \sin^n bx \,\mathrm{d} x = \frac{1}{a^2 + b^2 n^2} e^{ax} \sin^{n-1} bx \left( a \sin bx - n b \cos bx \right) + \frac{n (n-1) b^2}{a^2 + b^2 n^2} \int e^{ax} \sin^{n-2} bx \,\mathrm{d} x$ |
| 299 | + |
| 300 | +131. $\int e^{ax} \cos^n bx \,\mathrm{d} x = \frac{1}{a^2 + b^2 n^2} e^{ax} \cos^{n-1} bx \left( a \cos bx + n b \sin bx \right) + \frac{n (n-1) b^2}{a^2 + b^2 n^2} \int e^{ax} \cos^{n-2} bx \,\mathrm{d} x$ |
| 301 | + |
| 302 | +## (十四) 含有对数函数的积分 |
| 303 | + |
| 304 | +132. $\int \ln x \,\mathrm{d} x = x \ln x - x + C$ |
| 305 | + |
| 306 | +133. $\int \frac{\mathrm{d} x}{x \ln x} = \ln |\ln x| + C$ |
| 307 | + |
| 308 | +134. $\int x^n \ln x \,\mathrm{d} x = \frac{1}{n+1} x^{n+1} \left( \ln x - \frac{1}{n+1} \right) + C$ |
| 309 | + |
| 310 | +135. $\int (\ln x)^n \,\mathrm{d} x = x (\ln x)^n - n \int (\ln x)^{n-1} \,\mathrm{d} x$ |
| 311 | + |
| 312 | +136. $\int x^m (\ln x)^n \,\mathrm{d} x = \frac{1}{m+1} x^{m+1} (\ln x)^n - \frac{n}{m+1} \int x^m (\ln x)^{n-1} \,\mathrm{d} x$ |
| 313 | + |
| 314 | +## (十五) 含有双曲函数的积分 |
| 315 | + |
| 316 | +137. $\int \operatorname{sh} x \,\mathrm{d} x = \operatorname{ch} x + C$ |
| 317 | + |
| 318 | +138. $\int \operatorname{ch} x \,\mathrm{d} x = \operatorname{sh} x + C$ |
| 319 | + |
| 320 | +139. $\int \operatorname{th} x \,\mathrm{d} x = \ln \operatorname{ch} x + C$ |
| 321 | + |
| 322 | +140. $\int \operatorname{sh}^2 x \,\mathrm{d} x = -\frac{x}{2} + \frac{1}{4} \operatorname{sh} 2x + C$ |
| 323 | + |
| 324 | +141. $\int \operatorname{ch}^2 x \,\mathrm{d} x = \frac{x}{2} + \frac{1}{4} \operatorname{sh} 2x + C$ |
| 325 | + |
| 326 | +## (十六) 定积分 |
| 327 | + |
| 328 | +142. $\int_{-\pi}^{\pi} \cos nx \,\mathrm{d} x = \int_{-\pi}^{\pi} \sin nx \,\mathrm{d} x = 0$ |
| 329 | + |
| 330 | +143. $\int_{-\pi}^{\pi} \cos mx \sin nx \,\mathrm{d} x = 0$ |
| 331 | + |
| 332 | +144. $\int_{-\pi}^{\pi} \cos mx \cos nx \,\mathrm{d} x = \begin{cases} |
| 333 | + 0, & m \neq n, \\ |
| 334 | + \pi, & m = n. |
| 335 | + \end{cases}$ |
| 336 | + |
| 337 | +145. $\int_{-\pi}^{\pi} \sin mx \sin nx \,\mathrm{d} x = \begin{cases} |
| 338 | + 0, & m \neq n, \\ |
| 339 | + \pi, & m = n. |
| 340 | + \end{cases}$ |
| 341 | + |
| 342 | +146. $\int_{0}^{\pi} \sin mx \sin nx \,\mathrm{d} x = \int_{0}^{\pi} \cos mx \cos nx \,\mathrm{d} x = \begin{cases} |
| 343 | + 0, & m \neq n, \\ |
| 344 | + \frac{\pi}{2}, & m = n. |
| 345 | + \end{cases}$ |
| 346 | + |
| 347 | +147. $I_n = \int_{0}^{\frac{\pi}{2}} \sin^n x \,dx = \int_{0}^{\frac{\pi}{2}} \cos^n x \,dx$ |
| 348 | + |
| 349 | + $I_n = \frac{n-1}{n} I_{n-2}$ |
| 350 | + |
| 351 | + $= \begin{cases} |
| 352 | + \frac{n-1}{n} \cdot \frac{n-3}{n-2} \cdot \, \cdots \, \cdot \frac{4}{5} \cdot \frac{2}{3} & (n \text{ 为大于 }1\text{ 的正奇数}), & I_1 = 1, \\ |
| 353 | + \frac{n-1}{n} \cdot \frac{n-3}{n-2} \cdot \, \cdots \, \cdot \frac{3}{4} \cdot \frac{1}{2} \cdot \frac{\pi}{2} & (n \text{ 为正偶数}), & I_0 = \frac{\pi}{2}. |
| 354 | + \end{cases}$ |
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