Help with simplifying a trigonometric expression

Question

Could anyone help simplify this expression, $$\dfrac{\sin^{(-1)}\left(\dfrac{\sin(90)\sqrt{\frac1{\pi}-0.25}}{\sqrt{\frac1{\pi}}}\right)}{360}-0.5\sqrt{\frac1{\pi}-0.25} $$

It's in degrees.

Answer 1

$\begin{array}\\ \dfrac{\arcsin\left(\dfrac{\sin(90)\sqrt{\frac1{\pi}-0.25}}{\sqrt{\frac1{\pi}}}\right)}{360}-0.5\sqrt{\frac1{\pi}-0.25} &=\dfrac{\arcsin\left(\dfrac{\sqrt{\frac1{\pi}-0.25}}{\sqrt{\frac1{\pi}}}\right)}{2\pi}-0.5\sqrt{\frac1{\pi}-0.25} \qquad\text{converting to radians}\\ &=\dfrac{\arcsin\left(\sqrt{1-\pi/4}\right)}{2\pi}-0.5\sqrt{\frac1{\pi}-0.25}\\ \\ &=-0.054022154... \qquad\text{according to Wolfy}\\ \end{array} $