(x-y)d(ln(x-y))为什么等于dx-dy?看不懂T^T!

问题描述:

(x-y)d(ln(x-y))为什么等于dx-dy?看不懂T^T!

(x-y)d(ln(x-y))
=(x-y)*1/(x-y)*d(x-y)
=d(x-y)
=dx-dy