lim(n-->∞)∫0到1nx/(1+n^2x^4)dx =lim(n-->∞)1/2∫0到1/(1+n^2x^4)d(nx ^2)
=lim(n-->∞)1/2arctan(nx ^2)|(0,1)
=lim(n-->∞)1/2arctan(n)=π/4
同样问题怎么发了两遍啊?
lim(n-->∞)∫0到1nx/(1+n^2x^4)dx =lim(n-->∞)1/2∫0到1/(1+n^2x^4)d(nx ^2)
=lim(n-->∞)1/2arctan(nx ^2)|(0,1)
=lim(n-->∞)1/2arctan(n)=π/4
同样问题怎么发了两遍啊?