Menu Close

What-do-we-mean-by-f-x-dx-




Question Number 66293 by Rio Michael last updated on 12/Aug/19
What do we mean by      ∫_(−∞) ^(+∞) f(x) dx?
$${What}\:{do}\:{we}\:{mean}\:{by}\:\: \\ $$$$\:\:\int_{−\infty} ^{+\infty} {f}\left({x}\right)\:{dx}? \\ $$
Commented by mathmax by abdo last updated on 12/Aug/19
∫_(−∞) ^(+∞) f(x)dx =lim_(ξ→+∞)   ∫_(−ξ) ^ξ f(x)dx  and ∫_(−ξ) ^ξ f(x)dx is the surface  limiteted by y=0(  (x^′ ox)) and y=f(x)
$$\int_{−\infty} ^{+\infty} {f}\left({x}\right){dx}\:={lim}_{\xi\rightarrow+\infty} \:\:\int_{−\xi} ^{\xi} {f}\left({x}\right){dx}\:\:{and}\:\int_{−\xi} ^{\xi} {f}\left({x}\right){dx}\:{is}\:{the}\:{surface} \\ $$$${limiteted}\:{by}\:{y}=\mathrm{0}\left(\:\:\left({x}^{'} {ox}\right)\right)\:{and}\:{y}={f}\left({x}\right) \\ $$
Commented by mathmax by abdo last updated on 12/Aug/19
on]−ξ,ξ[...
$$\left.{on}\right]−\xi,\xi\left[…\right. \\ $$
Commented by Rio Michael last updated on 13/Aug/19
thanks
$${thanks} \\ $$

Leave a Reply

Your email address will not be published. Required fields are marked *