Calculates the inverse trigonometric cosine function (arccosine). Angle units are in radians. The function is defined for complex values. Phase of a complex number is evaluated between - π and π . If x is complex, or abs(x) > 1, the following equation is used:
$$ \text{acos}(x) = -i\ln(x+i\sqrt{1-x^2}) $$
|
Syntax |
Description |
|---|---|
|
out = acos(x); |
Returns the complex arccosine of x. |
Example
Calculate acos( π /4 + i).
x=pi/4+1i; ?acos(x); result: 1.03351-0.992724i
See Also