这道积分怎化简
来源:学生作业帮 编辑:搜搜做题作业网作业帮 分类:数学作业 时间:2024/08/08 21:44:50
这道积分怎化简
![](http://img.wesiedu.com/upload/4/c6/4c6f1c4f90cb82f3abf8b968557f148a.jpg)
![](http://img.wesiedu.com/upload/4/c6/4c6f1c4f90cb82f3abf8b968557f148a.jpg)
![这道积分怎化简](/uploads/image/z/20216731-67-1.jpg?t=%E8%BF%99%E9%81%93%E7%A7%AF%E5%88%86%E6%80%8E%E5%8C%96%E7%AE%80%26nbsp%3B)
∫(0,1) x√(1+4x^2) dx
=(1/2)*∫(0,1) √(1+4x^2) d(x^2)
=(1/8)*∫(0,1) √(1+4x^2) d(4x^2)
=(1/8)*∫(0,1) (1+4x^2)^(1/2) d(4x^2+1)
=(1/8)*(2/3)*(1+4x^2)^(3/2) | (0,1)
=(1/12)*(5^(3/2)-1)
有不懂欢迎追问
=(1/2)*∫(0,1) √(1+4x^2) d(x^2)
=(1/8)*∫(0,1) √(1+4x^2) d(4x^2)
=(1/8)*∫(0,1) (1+4x^2)^(1/2) d(4x^2+1)
=(1/8)*(2/3)*(1+4x^2)^(3/2) | (0,1)
=(1/12)*(5^(3/2)-1)
有不懂欢迎追问