Question

tim so tu nhien n thoa man: n+30 và n-11 ddeu la binh phuong cua 1 so tu nhien 

 

Answer 1

ta có:n+30=a^2

        n-11=b^2

=>n+30-n+11=a²-b²

=>41=(a-b)(a+b)

mà41=41*1

=>a-b=1;a+b=41=>a=21=>n=411

                         b=10=>n=411