sum from n=0 to infinity of (-5x)^n

解答

n = 0 \sum \infty (- 5 x)^{n}

收敛区间为 - \frac{1}{5} < x < \frac{1}{5}

求解步骤

n = 0 \sum \infty (- 5 x)^{n}

使用根值审敛法计算收敛区间

收敛区间为 - \frac{1}{5} < x < \frac{1}{5}

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