49. jn--a+号邮F-+c 50. 应可 51. *C -arccos 52. dx --d.c 5.小-adk=F-a-号nr+原-a+c s4.S-ya-x-sc 5.∫R-adr=}-arT+c s.-as-e--m+c 7.j=F--a+C gk-区r+原-可c (八)含有Va-x2(a>0)的积分 dx dx48. 2 2 3 d ( ) x x x a = 2 2 1 C x a 49. 2 2 2 d x x x a = 2 2 2 2 2 ln 2 2 x a x a x x a C 50. 2 2 2 3 d ( ) x x x a = 2 2 2 2 ln x x x a C x a 51. 2 2 dx x x a = 1 arccos a C a x 52. 2 2 2 dx x x a = 2 2 2 x a C a x 53. 2 2 x a x d = 2 2 2 2 2 ln 2 2 x a x a x x a C 54. 2 2 3 ( ) d x a x = 2 2 2 2 4 2 2 3 (2 5 ) ln 8 8 x x a x a a x x a C 55. 2 2 x x a x d = 1 2 2 3 ( ) 3 x a C 56. 2 2 2 x x a x d = 4 2 2 2 2 2 2 (2 ) ln 8 8 x a x a x a x x a C 57. 2 2 d x a x x = 2 2 arccos a x a a C x 58. 2 2 2 d x a x x = 2 2 2 2 ln x a x x a C x (八)含有 2 2 a x ( 0) a 的积分 59. 2 2 dx a x =arcsin x C a 60. 2 2 3 d ( ) x a x = 2 2 2 x C a a x