f(x)=e^a*x*sin(b*x) (a,b为常数) f(x)的n阶求导(届时x=0)
问题描述:
f(x)=e^a*x*sin(b*x) (a,b为常数) f(x)的n阶求导(届时x=0)
答
莱布尼兹公式(uv)^(n)=u^(n)v+C(1,n)u^(n-1)v'+...+C(k,n)u^(n-k)v^(k)+...+uv^(n)=ΣC(k,n)u^(n-k)v^(k) k=0到n其中:C(k,n)是组合数,k在上,n在下.[sin(bx)]^(k)=(b^k)sin(bx+kπ/2),将x=0代入后为:(b^k)sin(kπ/2...