If `cos(2sin^(-1)x)=1/9,` then find the values of `xdot`

Explanation

`cos(2sin^(-1)x)=1/9`

Let ` sin^(-1)x=alpha`

`x=sinalpha`
`cos(2alpha)=1/9`

`1-2sin^2alpha=1/9`

`1-1/9=2sin^2alpha`

`2sin^2alpha=8/9`

`sin^2alpha=4/9`

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