sum from n=0 to infinity of ((-1)/3)^{2n}

解答

n = 0 \sum \infty (\frac{- 1}{3})^{2 n}

收敛

求解步骤

n = 0 \sum \infty (\frac{- 1}{3})^{2 n}

使用级数比值审敛法:

收敛

= 收敛

\int \frac{23}{x ^{3} - 125} d x

d er i v a t i v e h (x) = \frac{3}{x ^{2}} + \frac{5}{x ^{4}}

x y^{^{'}} - 2 y = 7 x^{2}

d er i v a t i v e \frac{9 - x ^{2}}{4 x}

d er i v a t i v e f (x) = (x + 1) (2 x - 1)