The following composition of trigonometric buttons, such as sin, cos, tan, sin−1, cos−1, tan−1, can be used to replace the broken reciprocal button on a calculator.
 a)    sin− 1 tan cos tan− 1
  b)   tan− 1 sin tan− 1 cos
  c)    tan sin− 1 cos tan− 1
  d)   cos− 1 sin cos− 1 tan