Difficult. According to the information of official website of Henan University, it is difficult for mathematics graduate students in Henan University to master all the knowledge of mathematics, which is also determined by the school's doctoral admission qualification. The number of doctoral students is limited, and the requirements for scientific research level and achievements are relatively high. Henan University, referred to as "Heda University" for short, is a university jointly established by the people's government of Henan Province, the people of China and the Ministry of Education. It is the first batch of "double first-class" world-class discipline construction universities in China.