19 Test file number 123

  19.1 Problem number 242
  19.2 Problem number 243
  19.3 Problem number 255
  19.4 Problem number 257
  19.5 Problem number 258
  19.6 Problem number 260
  19.7 Problem number 262
  19.8 Problem number 263
  19.9 Problem number 264
  19.10 Problem number 266
  19.11 Problem number 267
  19.12 Problem number 268
  19.13 Problem number 537
  19.14 Problem number 549
  19.15 Problem number 554
  19.16 Problem number 555
  19.17 Problem number 556
  19.18 Problem number 557
  19.19 Problem number 561

Test folder name:

test_cases/4_Trig_functions/4.5_Secant/123_4.5.3.1-a+b_sec-^m-d_sec-^n-A+B_sec-