A12.1.4 下列级数中,收敛的级数是 __-|||-(A) sum _(n=1)^infty =dfrac (-2)(n) (B) sum _(n=1)^infty dfrac (1)(n+100); (C) sum _(n=1)^infty ((-1))^n+1(dfrac (1)(n)+dfrac (1)(n+1)); (D) sum _(n=1)^infty (dfrac (1)({n)^2}+dfrac (1)(n)).

(4)下列级数中,条件收敛的级数为 () .-|||-(A) sum _(n=1)^infty ((dfrac {1+3i)(2))}^n (B) sum _(

证明：级数sum _(n=1)^infty (sin dfrac (1)({n)^2})收敛。证明：级数收敛。

) ,若级数 sum _(n=1)^infty (a)_(n),sum _(n=1)^infty (b)_(n) 收敛,则 sum _(n=1)^infty (

下列级数绝对收敛的是()A.sum _(n=1)^infty dfrac ({(-1))^n+1}(2n+1)B.sum _(n=1)^infty dfrac

1.求下列幂级数的收敛域(或收敛圆):-|||-(1) sum _(n=1)^infty dfrac (1)({2)^n}(x)^2n-1;-|||-(2) s

设幂级数sum _(n=1)^infty (a)_(n)((x-2))^n在sum _(n=1)^infty (a)_(n)((x-2))^n处收敛，则此幂级数

幂级数sum _(n=1)^infty dfrac ({(-1))^n}(2n-1)(x)^2n-1(|x|lt 1)的和函数sum _(n=1)^infty

,求幂级数 sum _(n=1)^infty dfrac (2n-1)({2)^n}(x)^2n-2 的和函数,并求级数 sum _(n=1)^infty df

求级数sum _(n=1)^infty dfrac ({4)^n}(2+{n)^3}(x)^n的收敛区间?求级数的收敛区间?

4、求幂级数 sum _(n=1)^infty dfrac ({(-1))^n}(n)((x-1))^n 的收敛域.