The inverse cosine of *z* in Math. Defined by

Real part on the real axis:

Imaginary part on the real axis:

Real part on the imaginary axis is \( \displaystyle \frac{\pi}{2} \) .

Imaginary part on the imaginary axis:

Real part on the complex plane:

Imaginary part on the complex plane:

Absolute value on the complex plane:

Function category: circular functions