7 56. sec0 - cos0 = tan A sin 0 7 cott 7 57. cott + 1 1 + tant 58. cost - sint = 2 cos2t - 1 7 59. = 2 sec- t 1 - sin t 1 + sin z 7 60. coto + tan0 = csco sec 0 61. csc t + cott 8 = (cset + cott)2 cset - cott A csc t csc t 62. = 2 sec- 1 1 + csc t 1 - csc t 8 cost 63. = 1 + sin t 1 - sin t 64. cact + sect 2 tant 65. 1 - sin 0 sin t 1 + sino cos-0 66. 2 sin t + 3 sint - 2 sin t + 2 = 2 sin t - 1 67. V1 - sin20 = cos0, where 0 is acute 8 82. 83 627 4 FEB68. V sec- 0 - 1 = tan0, where 0 is acute 1 + 2 sinx + sin x 1 + sin x 69. cost x 1 - sin x tant - cott 70. = sec2 t - csc2 t sin t cost 71. (1 - cos2 x) (1 + cos2x) = 2 sin~x - sin* x 72. sin*x - costx = 2 sin2 x - 1 Exercises 73-80: Verify the identity. If you have a graph calculator, give graphical or numerical support. 73. coto sin0 = cost 74. tand cos0 = sin 0 CHECKING BASIC CONCEPTS FOR SECTIO 1. Determine the quadrant containing 0 if cote > and sin 0