sum from n=0 to infinity of ((x+9)/2)^n

解答

n = 0 \sum \infty (\frac{x + 9}{2})^{n}

收敛半径为 2, 收敛区间为 - 11 < x < - 7

求解步骤

n = 0 \sum \infty (\frac{x + 9}{2})^{n}

使用根值审敛法计算收敛区间

收敛半径为 2, 收敛区间为 - 11 < x < - 7

\frac{\partial}{\partial r} (r ln (r s^{2} t^{3}))

x \to + 1 lim (x (x - 2))

\frac{d}{d x} (sin (2 arcsin (x)))

x \to 0 lim (x - \frac{4}{x})

(2 y + 3 x) d x + x d y = 0