Please help in Russian's Chinese foreign student to explain, thanked student, Please, Chinese, Russian, explain

I want to ask that or is studies the management after the university economy mathematics to be difficult? Although my high school mathematics also good, but already had lost 5 years, did not know that can learn?

thank you very much

are you a chinese? or it's not possible to type chinese characters on your PC?
anyway,i can copy your questions to the chinese page for answer cos i am in china as well.