If and y = sin–1 (sin x), find


For ,


y=sin-1 (sin x)


= sin-1 ( sin (π –(π -x))


(to get y in principal range of sin-1 x)


i.e.,


y = π - x



From the last problem we see that and


So, y is not differentiable at


Extending this, we can say that y is not differentiable at x = (2n+1)


So, for


(Ans)


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