How to find inverse of functions like sinc x or signum x or any other functions like this. sinc x= sin x/x signum x = 1 for x0 =-1 for x

Question

How to find inverse of functions like sinc x or signum x or any other functions like this.

sinc x= sin x/x
signum x = 1 for x>0
                =-1 for x<0

anonymous · Answer

for signum just replace x and y

hartnn · Answer

so what would be its inverse ?

hartnn · Answer

and for that i should be 1st able to get x in terms of y

anonymous · Answer

inverse of signum is not a function (think of its graph)

anonymous · Answer

That y=sin(x)/x one is kinda tricky, so far I have
let w=y^-1, the inverse.
w=sin^-1(x*w)

turingtest · Answer

hartnn · Answer

so i would just assume inverse functions cannot be written as simple equations and close this.