# Math Help - inverse of x+sin(X)

1. ## inverse of x+sin(X)

i want to know how calculate the inverse of x+sin(x).
thanks

2. Originally Posted by horak
i want to know how calculate the inverse of x+sin(x).
thanks
We can show the inverse exists by working with the fact that $( x + \sin x) ' > 0$ for $x\not = \pi n$ and $0$ for $x=\pi n$. Therefore, the function is increasing. But to since the inverse you need to be able to solve the equation $y + \sin (y) = x$. I do not think there is a "nice" way to solve this equation.