Hi Dear...you are talking about top Universities of India. There is no comparison between the two. Both are best. If you have any confusion then go through the syllabus of both the universities and then decide because then only  will you will able to judge what is good for you.

According to the reports of India Today , BHU witnessed more than 67,000 registration for BHU Math's in 2018.BHU provides an awesome atmosphere for Students. Many Students of B.Sc maths group are placed in I.I.Ts, I.I.Ms, IISERs, and IISc- Bangalore. Admission is BHU is truely based on the scores obtained in entrance test.

Teacher's at DU are excellent and Alumni's of DU highly recommend B.Sc from D.U