integral from 4 to infinity of e^{-y/2}

解答

\int_{4}^{\infty} e^{- \frac{y}{2}} d y

\frac{2}{e ^{2}}

十进制

0.27067 \dots

求解步骤

\int_{4}^{\infty} e^{- \frac{y}{2}} d y

计算不定积分:

\int e^{- \frac{y}{2}} d y = - 2 e^{- \frac{y}{2}} + C

带入上下限计算后得:

\int_{4}^{\infty} e^{- \frac{y}{2}} d y = 0 - (- \frac{2}{e ^{2}})

= 0 - (- \frac{2}{e ^{2}})

化简

= \frac{2}{e ^{2}}

\int (sin (5 x) sin (x)) d x

\int \frac{x}{2 ( x + 1 ) 2 x + 1} d x

\frac{d}{d x} (\frac{x ^{3}}{3} - \frac{3}{x ^{5}} + 4 π)

\frac{d y}{d x} = \frac{( 4 y lo g _{e} ( x ) )}{x}

t an g e n t - 3 cos (x), at x = \frac{π}{2}