If the differential equation obtained by eliminating A,B from  $y={\left({\sin }^{-1}x\right)}^2+A$${\cos }^{-1}x+B$ is  $\left(a-x^2\right)y^{11}-x{y}^1=b$ then  $\frac{b+a}{b-a}$

$y={\left({\sin }^{-1}x\right)}^2+A{\cos }^{-1}x+B$

$y_1=2{\sin }^{-1}x\left(\frac{1}{\sqrt{1-x^2}}\right)+\frac{-A}{\sqrt{1-x^2}}$

$y_1\sqrt{1-x^2}=2{\sin }^{-1}x-A$

Again diff w.r.t x

$y_1\frac{1}{2\sqrt{1-x^2}}\left(-2x\right)+\sqrt{1-x^2}{y}_2=\frac{2}{\sqrt{1-x^2}}$

$\left(1-x^2\right)y_2-x{y}_1=2$

$a=1,b=2$