# What does the exponentiated generator of scale transformation do when it acts on a function? [duplicate]

We know that $$d/dx$$ is the generator of translation in the sense that $$e^{ad/dx}f(x)=f(x+a)\tag{1}$$ which can be easily be proved from the Taylor series of $$f(x+a)$$.

Studying the very basics of conformal group/transformations suggest that the generator of scale transformation, at least in 3D, is given by $$x_i\partial_i$$ (summed over $$i$$). Can we assume that the generator of scale transformation is given by $$x\frac{d}{dx}$$ in 1D? If so, can we in a similar way prove that, the action of $$e^{\lambda x \frac{d}{dx}}$$ on a function $$f(x)$$ gives $$f(e^{\lambda} x)$$?

Hint: Rewrite the dilation operator $$x\frac{d}{dx}~=~\frac{d}{d\ln |x|}$$ as a translation operator, and use OP's Taylor formula/translation eq. (1) to deduce that $$e^{\lambda x \frac{d}{dx}}f(x)~=~f(e^{\lambda}x).$$