What is the integral from 0 to infinity of xλe^{-λx} ?

The integral from 0 to infinity of xλe^{-λx} is 1/λ

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

integral from 0 to infinity of xλe^{-λx}

\int_{0}^{\infty} x λ e^{- λ x} d x

\frac{1}{λ}

Solution steps

\int_{0}^{\infty} x λ e^{- λ x} d x

Compute the indefinite integral:

\int x λ e^{- λ x} d x = - e^{- λ x} x - \frac{e ^{- λ x}}{λ} + C

Compute the boundaries:

\int_{0}^{\infty} x λ e^{- λ x} d x = 0 - (- \frac{1}{λ})

= 0 - (- \frac{1}{λ})

Simplify

= \frac{1}{λ}

What is the integral from 0 to infinity of xλe^{-λx} ?
The integral from 0 to infinity of xλe^{-λx} is 1/λ