# Transforming inverse trigonometric functions into logarithms: atrig2ln

### 5.23.22 Transforming inverse trigonometric functions into logarithms: atrig2ln

Just as the trigonometric functions can be written in terms of complex exponentials, the inverse trigonometric functions can be written in terms of complex logarithms. The atrig2ln command does this rewriting.

- atrig2ln takes one argument: expr, an expression containing inverse trigonometric functions.
- atrig2ln(expr) returns expr with any inverse trigonometric functions replaced by the appropriate complex logarithms.

#### Example.

Input:

atrig2ln(asin(x))

Output:

i ln

⎛
⎜
⎝

x+

√

x2−1

⎞
⎟
⎠

+

π
2