请教高数中一道题，图中划线的部分是怎么来的？
1个回答
展开全部
x³+[(1-x^3)^(1/3)]³ = (x+(1-x^3)^(1/3))(x²-x(1-x^3)^(1/3)+(1-x^3)^(2/3))
lim(x→∞) (x+(1-x^3)^(1/3))=lim(x→∞) {x³+[(1-x^3)^(1/3)]³}/(x²-x(1-x^3)^(1/3)+(1-x^3)^(2/3))
=lim(x→∞) [x³+(1-x^3)]/(x²-x(1-x^3)^(1/3)+(1-x^3)^(2/3))
=lim(x→∞) 1/(x²-x(1-x^3)^(1/3)+(1-x^3)^(2/3))
=lim(x→∞) (1/x²) / (1-(1/x^3-1)^(1/3)+(1/x^3-1)^(2/3))
=0/(1+1+1)
=0
lim(x→∞) (x+(1-x^3)^(1/3))=lim(x→∞) {x³+[(1-x^3)^(1/3)]³}/(x²-x(1-x^3)^(1/3)+(1-x^3)^(2/3))
=lim(x→∞) [x³+(1-x^3)]/(x²-x(1-x^3)^(1/3)+(1-x^3)^(2/3))
=lim(x→∞) 1/(x²-x(1-x^3)^(1/3)+(1-x^3)^(2/3))
=lim(x→∞) (1/x²) / (1-(1/x^3-1)^(1/3)+(1/x^3-1)^(2/3))
=0/(1+1+1)
=0
本回答由网友推荐
已赞过
已踩过<
评论
收起
你对这个回答的评价是？
推荐律师服务：
若未解决您的问题，请您详细描述您的问题，通过百度律临进行免费专业咨询
