Question

Cho a, b thuộc N* . Hãy so sánh \(\frac{a+n}{b+n}và\frac{a}{b}\)

Answer 1

Từ \(\frac{a}{b}\)> 1, Suy ra: ​an < bn

                        Suy ra:  an + ab < bn + ab

                        Suy ra: a (n + b) < b (n + a)

                        Suy ra: \(\frac{a}{b}\)> \(\frac{a+n}{b+n}\)

Answer 2

Nhầm, Suy ra: an > bn

            Suy ra: an + ab > bn + ab

            Suy ra: a (n + b) > b (n + a)

Answer 3

nếu a=b=>\(\frac{a+n}{b+n}\)=\(\frac{a}{b}\)

nếu a>b=>\(\frac{a+n}{b+n}\)>\(\frac{a}{b}\)

nếu a<b=>\(\frac{a+n}{b+n}\)<\(\frac{a}{b}\)