y=sin^-1(1/x)
let u=1/x
du/dx = -1/x^2
dy/du = 1/\sqrt{1-u^2}
dy/du \times du/dx
dy/dx= -1/x^2(\sqrt{1-u^2})
but u = 1/x
dy/dx = -1/x^2(\sqrt{1-(1/x)^2})
dy/dx = -1/x^2(\sqrt{x^2-1/x^2}
but \sqrt{x^2}= x
dy/dx = -1/x(\sqrt{x^2-1}
first time using latex =[