sum from n=6 to infinity of e^{3-2n}

解答

n = 6 \sum \infty e^{3 - 2 n}

收敛

求解步骤

n = 6 \sum \infty e^{3 - 2 n}

化简

e^{3 - 2 n} : e^{3} e^{- 2 n}

= n = 6 \sum \infty e^{3} e^{- 2 n}

使用常数相乘法则:

\sum c \cdot a_{n} = c \cdot \sum a_{n}

= e^{3} \cdot n = 6 \sum \infty e^{- 2 n}

使用级数比值审敛法:

收敛

= e^{3} 收敛

= 收敛

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