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long19590
![](https://blog.hocmai.vn/wp-content/uploads/2017/07/hot.gif)
![](https://blog.hocmai.vn/wp-content/uploads/2017/07/hot.gif)
giup minh voi minh khong hieu o vi du 2 phuong phap tich phan dang doi bien loai 2[thay khai], minh thay de cho; x+cosxdx/4-sinx mu 2.chu co phai la;[x+cosx]dx/4-sĩn mu 2.vay ma thay phan tich [xdx+cosdx]/4-sĩn mu 2.