The number of real solutions of the equation ${\sin }^{-1}\left(\sum _{i=1}^{\infty }{x}^{i+1}-x\sum _{i=1}^{\infty }{\left(\frac{x}{2}\right)}^i\right)=\frac{\pi }{2}-{\cos }^{-1}\left(\sum _{i=1}^{\infty }{\left(-\frac{x}{2}\right)}^i-\sum _{i=1}^{\infty }{\left(-x\right)}^i\right)$lying in the interval $\left(-\frac{1}{2},\frac{1}{2}\right)$is ____. (Here, the inverse trigonometric function $={\sin }^{-1}x$and ${\cos }^{-1}x$assume values in $\left[\frac{\pi }{2},\frac{\pi }{2}\right]$and $\left[0,\pi \right]$, respectively.)

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