求极限...帮我看看我解答的对不对就行了lim(x趋向0)sin(2x+5x^2)/(ln(e^x+x-x^2))=[sin(2x+5x^2)/(2x+5x^2)][(2x+5x^2)/(ln(e^x+x-x^2)]=(2x+5x^2)/ln(1+1/[1/(x-x^2)])^[1/(x-x^2)](x-x^2)=(2x+5x^2)/(x-x^2)=(2+5x)/(1-x)=-5
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/06 12:14:21
![求极限...帮我看看我解答的对不对就行了lim(x趋向0)sin(2x+5x^2)/(ln(e^x+x-x^2))=[sin(2x+5x^2)/(2x+5x^2)][(2x+5x^2)/(ln(e^x+x-x^2)]=(2x+5x^2)/ln(1+1/[1/(x-x^2)])^[1/(x-x^2)](x-x^2)=(2x+5x^2)/(x-x^2)=(2+5x)/(1-x)=-5](/uploads/image/z/8580273-33-3.jpg?t=%E6%B1%82%E6%9E%81%E9%99%90...%E5%B8%AE%E6%88%91%E7%9C%8B%E7%9C%8B%E6%88%91%E8%A7%A3%E7%AD%94%E7%9A%84%E5%AF%B9%E4%B8%8D%E5%AF%B9%E5%B0%B1%E8%A1%8C%E4%BA%86lim%28x%E8%B6%8B%E5%90%910%EF%BC%89sin%282x%2B5x%5E2%29%2F%EF%BC%88ln%28e%5Ex%2Bx-x%5E2%29%EF%BC%89%3D%5Bsin%282x%2B5x%5E2%29%2F%282x%2B5x%5E2%29%5D%5B%282x%2B5x%5E2%29%2F%EF%BC%88ln%28e%5Ex%2Bx-x%5E2%29%5D%3D%282x%2B5x%5E2%29%2Fln%EF%BC%881%2B1%2F%5B1%2F%28x-x%5E2%29%5D%EF%BC%89%5E%5B1%2F%28x-x%5E2%29%5D%28x-x%5E2%29%3D%282x%2B5x%5E2%29%2F%28x-x%5E2%29%3D%282%2B5x%29%2F%281-x%29%3D-5)
求极限...帮我看看我解答的对不对就行了lim(x趋向0)sin(2x+5x^2)/(ln(e^x+x-x^2))=[sin(2x+5x^2)/(2x+5x^2)][(2x+5x^2)/(ln(e^x+x-x^2)]=(2x+5x^2)/ln(1+1/[1/(x-x^2)])^[1/(x-x^2)](x-x^2)=(2x+5x^2)/(x-x^2)=(2+5x)/(1-x)=-5
求极限...帮我看看我解答的对不对就行了
lim(x趋向0)sin(2x+5x^2)/(ln(e^x+x-x^2))
=[sin(2x+5x^2)/(2x+5x^2)][(2x+5x^2)/(ln(e^x+x-x^2)]
=(2x+5x^2)/ln(1+1/[1/(x-x^2)])^[1/(x-x^2)](x-x^2)
=(2x+5x^2)/(x-x^2)
=(2+5x)/(1-x)=-5
求极限...帮我看看我解答的对不对就行了lim(x趋向0)sin(2x+5x^2)/(ln(e^x+x-x^2))=[sin(2x+5x^2)/(2x+5x^2)][(2x+5x^2)/(ln(e^x+x-x^2)]=(2x+5x^2)/ln(1+1/[1/(x-x^2)])^[1/(x-x^2)](x-x^2)=(2x+5x^2)/(x-x^2)=(2+5x)/(1-x)=-5
=[sin(2x+5x^2)/(2x+5x^2)][(2x+5x^2)/(ln(e^x+x-x^2)]
=(2x+5x^2)/ln(1+1/[1/(x-x^2)])^[1/(x-x^2)](x-x^2)
=(2x+5x^2)/(x-x^2)
这两个都没有看出为什么来
对(2x+5x^2)/(ln(e^x+x-x^2)利用罗比达法则得到
(2+10x) / [e^x + 1 -2x)/(e^x+x-x^2)]
=2/2=1,和你答案不同.因此我怀疑我看不懂的地方,你实际是弄错了